refactor: harden codebase and remove unicode artifacts

- fix urllib.parse.quote import (was urllib.request.quote)
- add operator precedence parens in generate_pack dedup check
- narrow bare except to specific types in batocera target scraper
- cache load_platform_config and build_zip_contents_index results
- add selective algorithm support to compute_hashes
- atomic write for fetch_large_file (tmp + rename)
- add response size limit to base scraper fetch
- extract build_target_cores_cache to common.py (dedup verify/pack)
- hoist _build_supplemental_index out of per-platform loop
- migrate function-attribute caches to module-level dicts
- add @abstractmethod to BaseTargetScraper.fetch_targets
- remove backward-compat re-exports from common.py
- replace em-dashes and unicode arrows with ASCII equivalents
- remove decorative section dividers and obvious comments

scripts/scraper/targets/batocera_targets_scraper.py

@@ -136,7 +136,7 @@ def _check_atom(tokens: list[str], pos: int, active: frozenset[str]) -> tuple[bo
     if tok.startswith('"'):
         pos += 1
         return True, pos
-    # Unknown token — treat as true to avoid false negatives
+    # Unknown token -treat as true to avoid false negatives
     pos += 1
     return True, pos
 

scripts/scraper/targets/emudeck_targets_scraper.py

@@ -1,8 +1,8 @@
 """Scraper for EmuDeck emulator targets.
 
 Sources:
-  SteamOS: dragoonDorise/EmuDeck — functions/EmuScripts/*.sh
-  Windows: EmuDeck/emudeck-we — functions/EmuScripts/*.ps1
+  SteamOS: dragoonDorise/EmuDeck -functions/EmuScripts/*.sh
+  Windows: EmuDeck/emudeck-we -functions/EmuScripts/*.ps1
 """
 from __future__ import annotations
 

scripts/scraper/targets/retroarch_targets_scraper.py

@@ -56,7 +56,7 @@ TARGETS: list[tuple[str, str, str]] = [
     ("nintendo/wiiu/latest", "nintendo-wiiu", "ppc"),
     ("playstation/ps2/latest", "playstation-ps2", "mips"),
     ("playstation/psp/latest", "playstation-psp", "mips"),
-    # vita: only VPK bundles on buildbot — cores listed via libretro-super recipes
+    # vita: only VPK bundles on buildbot -cores listed via libretro-super recipes
 ]
 
 # Recipe-based targets: (recipe_path_under_RECIPE_BASE_URL, target_name, architecture)