Stop tracking workspace/; bundled-demos/ is the canonical demo source

`workspace/` is runtime state (per-user folders, no-auth dev's `code/`)
and shouldn't be in git. The same files were previously committed under
both `workspace/code/` and `src/static/bundled-demos/`, which forced a
Docker `diff -q` sync check and leaked user-scoped paths into version
control.

- /workspace/ added to .gitignore; all previously tracked files removed
  via `git rm --cached`.
- src/static/bundled-demos/ becomes the single source of truth: panel16
  demos, led_tutorial, led_patterns, neopixel demos, and main.py move
  here alongside the existing canonical demos.
- New BUNDLED_DEMOS_DIR config; user_workspace seeders read from it.
- main.py lifespan seeds WORKSPACE_ROOT/code/ on startup so a fresh
  clone running `pipenv run dev` still gets the full sample set
  (existing files never overwritten — user edits survive restarts).
- Dockerfile drops `COPY workspace` and the diff sanity check.
- README/LED_TUTORIAL repointed at the new canonical paths.
- test_led_patterns loads led_patterns.py from bundled-demos.
- test_api uses mkdir(exist_ok=True) for `code/` (startup pre-creates).

Co-authored-by: Cursor <cursoragent@cursor.com>

src/static/bundled-demos/led_patterns.py

@@ -0,0 +1,143 @@
+"""LED pattern helpers inspired by embedded NeoPixel drivers."""
+
+from __future__ import annotations
+
+import random
+
+
+Color = tuple[int, int, int]
+
+
+def _clamp(channel: int) -> int:
+    return max(0, min(255, int(channel)))
+
+
+def wheel(pos: int) -> Color:
+    """Return a rainbow color for position 0-255."""
+    pos = 255 - (pos & 255)
+    if pos < 85:
+        return (_clamp(255 - pos * 3), 0, _clamp(pos * 3))
+    if pos < 170:
+        pos -= 85
+        return (0, _clamp(pos * 3), _clamp(255 - pos * 3))
+    pos -= 170
+    return (_clamp(pos * 3), _clamp(255 - pos * 3), 0)
+
+
+def rainbow_frame(led_count: int, frame: int, step: int = 4) -> list[Color]:
+    """Generate one rainbow frame across all LEDs."""
+    if led_count <= 0:
+        return []
+    return [wheel((i * 256 // led_count + frame * step) & 255) for i in range(led_count)]
+
+
+def chase_frame(
+    led_count: int,
+    frame: int,
+    color: Color = (255, 120, 0),
+    tail: Color = (16, 0, 0),
+) -> list[Color]:
+    """Generate a two-pixel chase pattern."""
+    if led_count <= 0:
+        return []
+    out: list[Color] = [(0, 0, 0) for _ in range(led_count)]
+    head = frame % led_count
+    trail = (head - 1) % led_count
+    out[trail] = tuple(_clamp(v) for v in tail)  # type: ignore[assignment]
+    out[head] = tuple(_clamp(v) for v in color)  # type: ignore[assignment]
+    return out
+
+
+def _bounce_head_index(led_count: int, frame: int) -> int:
+    """Map frame to a triangular index sweep 0..N-1..0 (Ping-Pong position)."""
+    if led_count <= 1:
+        return 0
+    span = led_count - 1
+    cycle = span * 2
+    if cycle <= 0:
+        return 0
+    t = frame % cycle
+    return t if t <= span else 2 * span - t
+
+
+def _bounce_phase_tail_direction(led_count: int, frame: int) -> int:
+    """Extend tail opposite motion: -1 fades toward lower indices, +1 toward higher."""
+    if led_count <= 1:
+        return -1
+    span = led_count - 1
+    cycle = span * 2
+    if cycle <= 0:
+        return -1
+    t = frame % cycle
+    if t <= span:
+        return -1
+    return 1
+
+
+def knight_rider_scanner_frame(
+    led_count: int,
+    frame: int,
+    head_color: Color = (220, 0, 28),
+    tail_len: int = 8,
+    falloff_gamma: float = 2.6,
+) -> list[Color]:
+    """KITT-style bouncing scanner: saturated head with exponential tail fading to off."""
+    if led_count <= 0:
+        return []
+    out: list[Color] = [(0, 0, 0) for _ in range(led_count)]
+    tl = max(1, tail_len)
+    head = _bounce_head_index(led_count, frame)
+    direc = _bounce_phase_tail_direction(led_count, frame)
+    gamma = max(1.05, falloff_gamma)
+    for rk in reversed(range(tl)):
+        idx = head + direc * rk
+        if idx < 0 or idx >= led_count:
+            continue
+        w = max(0.0, float(tl - rk) / float(tl))
+        strength = w**gamma
+        out[idx] = tuple(_clamp(int(head_color[ch] * strength)) for ch in range(3))
+    return out
+
+
+def scanner_bounce_frame(
+    led_count: int,
+    frame: int,
+    head_color: Color = (0, 220, 255),
+    tail_color: Color = (0, 40, 90),
+    tail_len: int = 5,
+) -> list[Color]:
+    """Ping-pong scanner: head reverses at both ends with a directional fading tail."""
+    if led_count <= 0:
+        return []
+    out: list[Color] = [(0, 0, 0) for _ in range(led_count)]
+    tl = max(1, tail_len)
+    for rk in reversed(range(tl)):
+        past = frame - rk
+        if past < 0:
+            continue
+        idx = _bounce_head_index(led_count, past)
+        strength = max(0.0, float(tl - rk) / float(tl))
+        if rk == 0:
+            out[idx] = tuple(_clamp(int(c)) for c in head_color)
+        else:
+            out[idx] = tuple(_clamp(int(tail_color[i] * strength)) for i in range(3))
+    return out
+
+
+def twinkle_frame(
+    led_count: int,
+    frame: int,
+    base: Color = (0, 0, 8),
+    sparkle: Color = (255, 255, 180),
+    sparkles: int = 3,
+    seed: int = 1337,
+) -> list[Color]:
+    """Generate deterministic twinkle frames for testing/replay."""
+    if led_count <= 0:
+        return []
+    out: list[Color] = [tuple(_clamp(v) for v in base) for _ in range(led_count)]  # type: ignore[list-item]
+    rng = random.Random(seed + frame)
+    for _ in range(min(max(0, sparkles), led_count)):
+        idx = rng.randrange(led_count)
+        out[idx] = tuple(_clamp(v) for v in sparkle)  # type: ignore[assignment]
+    return out

src/static/bundled-demos/led_tutorial.py

@@ -0,0 +1,50 @@
+"""LED tutorial script for NeoPixel in the browser editor.
+
+Run this file and watch the in-app NeoPixel simulator panel.
+"""
+
+from machine import Pin
+import neopixel
+import time
+
+
+LED_COUNT = 12
+np = neopixel.NeoPixel(Pin(4), LED_COUNT)
+
+
+def show_step(title: str):
+    print(f"\n--- {title} ---")
+
+
+show_step("Step 1: single colors")
+np.fill((0, 0, 0))
+np.write()
+time.sleep(0.2)
+np[0] = (255, 0, 0)  # red
+np[1] = (0, 255, 0)  # green
+np[2] = (0, 0, 255)  # blue
+np.write()
+time.sleep(0.8)
+
+show_step("Step 2: fill strip")
+np.fill((40, 0, 120))
+np.write()
+time.sleep(0.6)
+
+show_step("Step 3: moving pixel")
+for i in range(len(np)):
+    np.fill((0, 0, 0))
+    np[i] = (255, 120, 0)
+    np.write()
+    time.sleep(0.06)
+
+show_step("Step 4: simple pulse")
+for level in list(range(0, 200, 20)) + list(range(200, -1, -20)):
+    np.fill((level, 0, level // 3))
+    np.write()
+    time.sleep(0.05)
+
+show_step("Done")
+np.fill((0, 0, 0))
+np.write()
+print("Tutorial complete.")

src/static/bundled-demos/main.py

@@ -0,0 +1,3 @@
+"""Sample script — runs in the browser under Pyodide."""
+
+print("Hello from Pyodide")

src/static/bundled-demos/neopixel_demo.py

@@ -0,0 +1,12 @@
+"""Example ESP32 NeoPixel script using mock modules in browser."""
+
+from machine import Pin
+import neopixel
+
+
+np = neopixel.NeoPixel(Pin(4), 8)
+np.fill((0, 0, 0))
+np[0] = (255, 0, 0)
+np[1] = (0, 255, 0)
+np[2] = (0, 0, 255)
+np.write()

src/static/bundled-demos/neopixel_time_test.py

@@ -0,0 +1,32 @@
+"""NeoPixel time-based animation test for the browser simulator."""
+
+from machine import Pin
+import neopixel
+import time
+
+
+np = neopixel.NeoPixel(Pin(4), 50)
+
+
+def wheel(pos: int) -> tuple[int, int, int]:
+    """Generate rainbow colors across 0-255 positions."""
+    pos = 255 - (pos & 255)
+    if pos < 85:
+        return (255 - pos * 3, 0, pos * 3)
+    if pos < 170:
+        pos -= 85
+        return (0, pos * 3, 255 - pos * 3)
+    pos -= 170
+    return (pos * 3, 255 - pos * 3, 0)
+
+
+print("Starting NeoPixel time test...")
+for frame in range(60):
+    for i in range(len(np)):
+        np[i] = wheel((i * 256 // len(np) + frame * 4) & 255)
+    np.write()
+    time.sleep(0.08)
+
+np.fill((0, 0, 0))
+np.write()
+print("NeoPixel time test complete.")

src/static/bundled-demos/panel16_bounce.py

@@ -0,0 +1,41 @@
+"""16x16 bouncing pixel with fading trail."""
+
+from machine import Pin
+import neopixel
+import time
+
+from panel16_utils import PANEL_H, PANEL_W, clamp8, xy_to_index
+
+
+np = neopixel.NeoPixel(Pin(4), PANEL_W * PANEL_H)
+
+trail = [[0 for _ in range(PANEL_W)] for _ in range(PANEL_H)]
+x = 0
+y = 0
+vx = 1
+vy = 1
+
+for _frame in range(420):
+    for yy in range(PANEL_H):
+        for xx in range(PANEL_W):
+            trail[yy][xx] = max(0, trail[yy][xx] - 14)
+
+    trail[y][x] = 255
+
+    for yy in range(PANEL_H):
+        for xx in range(PANEL_W):
+            v = trail[yy][xx]
+            np[xy_to_index(xx, yy)] = (clamp8(v), clamp8(v // 2), clamp8(30))
+
+    np.write()
+    time.sleep(0.02)
+
+    x += vx
+    y += vy
+    if x <= 0 or x >= PANEL_W - 1:
+        vx *= -1
+    if y <= 0 or y >= PANEL_H - 1:
+        vy *= -1
+
+np.fill((0, 0, 0))
+np.write()

src/static/bundled-demos/panel16_matrix_rain.py

@@ -0,0 +1,37 @@
+"""16x16 matrix-style rain animation."""
+
+from machine import Pin
+import neopixel
+import random
+import time
+
+from panel16_utils import PANEL_H, PANEL_W, clamp8, xy_to_index
+
+
+np = neopixel.NeoPixel(Pin(4), PANEL_W * PANEL_H)
+rng = random.Random(42)
+
+heads = [rng.randrange(-PANEL_H, 0) for _ in range(PANEL_W)]
+
+for _frame in range(320):
+    for y in range(PANEL_H):
+        for x in range(PANEL_W):
+            np[xy_to_index(x, y)] = (0, 0, 0)
+
+    for x in range(PANEL_W):
+        heads[x] += 1
+        if heads[x] > PANEL_H + 6:
+            heads[x] = rng.randrange(-PANEL_H, 0)
+
+        head_y = heads[x]
+        for tail in range(8):
+            y = head_y - tail
+            if 0 <= y < PANEL_H:
+                brightness = clamp8(255 - tail * 36)
+                np[xy_to_index(x, y)] = (0, brightness, 0)
+
+    np.write()
+    time.sleep(0.045)
+
+np.fill((0, 0, 0))
+np.write()

src/static/bundled-demos/panel16_rainbow_wave.py

@@ -0,0 +1,33 @@
+"""16x16 rainbow wave animation."""
+
+from machine import Pin
+import neopixel
+import time
+
+from panel16_utils import PANEL_H, PANEL_W, clamp8, xy_to_index
+
+
+np = neopixel.NeoPixel(Pin(4), PANEL_W * PANEL_H)
+
+
+def wheel(pos: int) -> tuple[int, int, int]:
+    pos = 255 - (pos & 255)
+    if pos < 85:
+        return (clamp8(255 - pos * 3), 0, clamp8(pos * 3))
+    if pos < 170:
+        pos -= 85
+        return (0, clamp8(pos * 3), clamp8(255 - pos * 3))
+    pos -= 170
+    return (clamp8(pos * 3), clamp8(255 - pos * 3), 0)
+
+
+for frame in range(240):
+    for y in range(PANEL_H):
+        for x in range(PANEL_W):
+            color_pos = ((x * 10) + (y * 6) + frame * 5) & 255
+            np[xy_to_index(x, y)] = wheel(color_pos)
+    np.write()
+    time.sleep(0.04)
+
+np.fill((0, 0, 0))
+np.write()

src/static/bundled-demos/panel16_utils.py

@@ -0,0 +1,26 @@
+"""Helpers for 16x16 serpentine NeoPixel panel animations.
+
+Mapping matches the simulator's 16x16 mode:
+- first LED at top-right
+- row 0 goes right -> left
+- row 1 goes left -> right
+"""
+
+from __future__ import annotations
+
+
+PANEL_W = 16
+PANEL_H = 16
+
+
+def xy_to_index(x: int, y: int, width: int = PANEL_W) -> int:
+    """Map panel coordinate (x, y) to LED index."""
+    x = int(x)
+    y = int(y)
+    if y % 2 == 0:
+        return y * width + (width - 1 - x)
+    return y * width + x
+
+
+def clamp8(v: int) -> int:
+    return max(0, min(255, int(v)))