feat: configuration enablement — env-var defaults + source resilience

Six small additive changes that make the skill correctly understand its
configured sources, plus tests + docs.

User-visible benefits

- LAST30DAYS_STORE=1 in .env turns persistence default-on without
  remembering --store on every invocation. Mirrors LAST30DAYS_DEBUG /
  LAST30DAYS_SKIP_PREFLIGHT convention.
- SCRAPE_CREATORS_API_KEY (with underscore) accepted as alias for the
  canonical name. Matches the spelling used in the vendor's own example
  code (Adrian Horning's repo); saves the next user the same diagnostic
  rabbit hole.
- Bluesky search now hits api.bsky.app (canonical AppView) instead of
  public.api.bsky.app (BunnyCDN-blocked public mirror as of 2026-05-04).
  BSKY_SEARCH_HOST env var lets users self-rescue future host migrations
  without a code release. Pre-fix: silent 0 Bluesky posts on every run.
- App-password format validator emits a one-shot stderr warning when
  BSKY_APP_PASSWORD doesn't match xxxx-xxxx-xxxx-xxxx form. Detect-don't-
  gate: createSession still accepts main passwords; the warning helps
  users identify a hygiene issue without breaking existing setups.
- Instagram retry on multi-token 500. SC's v2 reels endpoint wraps
  Google Search and 500's frequently on multi-word queries; a hashtag-
  form retry runs once before bubbling up. Documented vendor instability.
- LAST30DAYS_TRANSCRIPT_TIMEOUT env var (default 30s, was hardcoded 15s).
  SC's transcript endpoint regularly takes >15s; the old default was
  clipping legitimate responses.
- Silent-failure visibility: new bonus_errored field in the quality
  nudge fires when SC is configured but Instagram returned 0 items.
  Users see "Bonus source silent: Instagram" instead of unexplained
  absence.
- YouTube degraded-ratio false-positive fixed. Captions-disabled videos
  can never produce a transcript regardless of yt-dlp version; they're
  now subtracted from the denominator so a single uploader-disabled
  video doesn't false-trigger the "stale yt-dlp" nudge.
- urllib retry path: status_code attribute typo fix. The Instagram
  500-retry was dead code on the urllib branch (getattr(e, 'status', ...)
  while http.HTTPError exposes status_code).

Docs

- README.md: added /plugin install last30days step after marketplace add
  in three places (the install was previously omitted in the docs).
- CONFIGURATION.md: documented LAST30DAYS_STORE env var, added
  BSKY_SEARCH_HOST + app-password format section, mentioned
  LAST30DAYS_TRANSCRIPT_TIMEOUT in the Instagram source row.

Test plan

- 43 new unit tests across test_bluesky.py, test_instagram_sc.py,
  test_quality_nudge.py, test_youtube_yt.py
- 141 total tests passing in target suite
- Verified end-to-end: /last30days "Toronto resale condo market" with
  all 11+ sources active stored 35 new + 5 updated findings, all builder-
  PR-style accounts absent (organic agent voice in Instagram + TikTok
  results)

Backward compatibility

All changes are strictly additive. Optional kwargs default to None.
New env vars are opt-in. Existing CLI flags untouched. Existing callers
of public functions unaffected.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

skills/last30days/scripts/last30days.py

@@ -908,7 +908,17 @@ def main() -> int:
         suppress_web_promo=bool(external_plan or comp_plan),
     )
     _write_last_run(topic, report)
-    if args.store:
+    # LAST30DAYS_STORE env var = persistence default-on. Read both os.environ
+    # (for shell-exported users) and config (for users who set it in
+    # ~/.config/last30days/.env, which env.py loads but does not propagate
+    # to os.environ). Mirrors the LAST30DAYS_DEBUG / LAST30DAYS_SKIP_PREFLIGHT
+    # convention; env-var or config wins, with `--store` flag still working.
+    _store_env = (
+        os.environ.get("LAST30DAYS_STORE")
+        or config.get("LAST30DAYS_STORE")
+        or ""
+    ).lower()
+    if args.store or _store_env in ("1", "true", "yes"):
         counts = persist_report(report)
         sys.stderr.write(
             f"[last30days] Stored {counts['new']} new, {counts['updated']} updated findings\n"
@@ -922,6 +932,7 @@ def main() -> int:
         # degraded-YouTube failure mode (videos returned but transcripts
         # silently failed - typically a stale yt-dlp binary).
         youtube_items = report.items_by_source.get("youtube") or []
+        instagram_items = report.items_by_source.get("instagram") or []
         research_results = {
             "youtube_videos_count": len(youtube_items),
             "youtube_transcripts_count": sum(
@@ -930,6 +941,17 @@ def main() -> int:
             ),
             "youtube_error": report.errors_by_source.get("youtube"),
             "x_error": report.errors_by_source.get("x"),
+            # Captions-disabled videos can never produce a transcript regardless
+            # of yt-dlp version; subtract them from the degraded-ratio
+            # denominator so a single uploader-disabled video does not trip the
+            # "stale yt-dlp" nudge.
+            "youtube_captions_disabled_count": sum(
+                1 for it in youtube_items if it.metadata.get("captions_disabled")
+            ),
+            # Track Instagram returned-zero-items so quality_nudge can detect
+            # the silent-failure case (SC configured but the v2 reels endpoint
+            # 500'd through both the original query and the hashtag retry).
+            "instagram_items_count": len(instagram_items),
         }
         quality = quality_nudge.compute_quality_score(config, research_results)
         if quality.get("nudge_text"):