chore(e2e): run the e2e dev server on native Linux

e2e.sh and gen_fixtures.py assumed WSL driving the Windows toolchain.
They now detect WSL (a microsoft kernel with cargo.exe available) and
otherwise use native tools:

- e2e.sh: cargo/curl instead of cargo.exe/curl.exe, pgrep/pkill
  instead of tasklist/taskkill, Linux paths in the generated .env, and
  binaries without the .exe suffix.
- gen_fixtures.py: picks the first ffmpeg that has the drawtext filter
  (a minimal build earlier on PATH may not; E2E_FFMPEG overrides), finds
  a monospace font with fc-match, and only translates paths with wslpath
  for .exe tools.
- Quote USER_NAME in the generated .env: the unquoted space made the
  dotenv parser reject the line.
- Mark the scripts executable.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

dev/e2e/gen_fixtures.py

@@ -8,8 +8,9 @@ in a single exiftool batch. A `manifest.json` next to the media records
 what was generated and what the server should derive from it, so tests
 can assert against it instead of hardcoding counts.
 
-The harness runs in WSL but the tools (ffmpeg.exe / exiftool.exe) are
-Windows binaries, so every path handed to them goes through `wslpath -w`.
+Runs on native Linux with ffmpeg / exiftool, or in WSL driving the Windows
+binaries (ffmpeg.exe / exiftool.exe), in which case every path handed to
+them goes through `wslpath -w`.
 
 Usage: gen_fixtures.py <out_dir> [--import DIR]
   <out_dir>/media/          the pristine library (never served directly)
@@ -30,11 +31,48 @@ from dataclasses import dataclass, field
 from pathlib import Path
 from zoneinfo import ZoneInfo
 
-FFMPEG = shutil.which("ffmpeg.exe") or shutil.which("ffmpeg")
+
+
+def _find_ffmpeg() -> str | None:
+    """The first ffmpeg that can burn labels in (has `drawtext`, i.e. was
+    built with freetype). E2E_FFMPEG overrides. Minimal builds earlier on
+    PATH (e.g. a custom one in ~/bin) often lack it."""
+    if os.environ.get("E2E_FFMPEG"):
+        return os.environ["E2E_FFMPEG"]
+    candidates = [shutil.which("ffmpeg.exe"), shutil.which("ffmpeg"), "/usr/bin/ffmpeg"]
+    for cand in dict.fromkeys(c for c in candidates if c and os.path.exists(c)):
+        try:
+            filters = subprocess.run(
+                [cand, "-hide_banner", "-filters"], capture_output=True, text=True
+            ).stdout
+        except OSError:
+            continue
+        if " drawtext " in filters:
+            return cand
+    return None
+
+
+FFMPEG = _find_ffmpeg()
 EXIFTOOL = shutil.which("exiftool.exe") or shutil.which("exiftool")
-# drawtext needs an explicit font on Windows ffmpeg builds. The colon after
-# the drive letter must be escaped inside a filter argument.
-FONT = "C\\:/Windows/Fonts/consola.ttf"
+
+def _font() -> str:
+    """A monospace font for ffmpeg's drawtext, as a filter-escaped path."""
+    if FFMPEG and FFMPEG.endswith(".exe"):
+        # Windows ffmpeg needs an explicit font; the colon after the drive
+        # letter must be escaped inside a filter argument.
+        return "C\\:/Windows/Fonts/consola.ttf"
+    try:
+        found = subprocess.check_output(
+            ["fc-match", "-f", "%{file}", "monospace"], text=True
+        ).strip()
+        if found:
+            return found
+    except (OSError, subprocess.CalledProcessError):
+        pass
+    return "/usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf"
+
+
+FONT = _font()
 
 # The owner's display zone and the server zone the e2e env pins (TZ=...).
 # Naive fixture datetimes without GPS are walls in this zone.
@@ -85,6 +123,10 @@ class Item:
 
 
 def win(p: Path) -> str:
+    """`p` as the external tools see it: a Windows path for WSL-driven
+    .exe tools, unchanged for native ones."""
+    if not (FFMPEG or "").endswith(".exe"):
+        return str(p)
     return subprocess.check_output(["wslpath", "-w", str(p)], text=True).strip()
 
 
@@ -288,7 +330,11 @@ def main() -> int:
                     help="also copy this folder (read-only source) into media/imported/")
     a = ap.parse_args()
     if not FFMPEG or not EXIFTOOL:
-        print("ffmpeg(.exe) and exiftool(.exe) must be on PATH", file=sys.stderr)
+        print(
+            "ffmpeg(.exe) with the drawtext filter (built with freetype) and "
+            "exiftool(.exe) must be on PATH; set E2E_FFMPEG to pick an ffmpeg",
+            file=sys.stderr,
+        )
         return 1
 
     out: Path = a.out_dir.resolve()