chore: bump version to 12.6.0

Minor release: 17 issues fixed and 4 foundations introduced via PR #2282.

Foundations (new public modules):
- F1 spawnHidden wrapper (src/shared/spawn.ts) — windowsHide default
- F2 paths namespace (src/shared/paths.ts) — 24 hardcoded sites collapsed,
  CLAUDE_MEM_DATA_DIR flows 100% of runtime
- F3 getUptimeSeconds (src/shared/uptime.ts) — fixes ms-bug at Server.ts:165
- F4 ClassifiedProviderError (src/services/worker/provider-errors.ts) — kind
  union (transient/unrecoverable/rate_limit/quota_exhausted/auth_invalid),
  per-provider classifiers, unrecoverablePatterns allowlist deleted

User-facing capabilities:
- OAuth keychain reader (#2215): readClaudeOAuthToken() reads from
  macOS keychain, Windows DPAPI, Linux libsecret at worker spawn-time
- Quota-aware wall-clock guard (#2234): RateLimitStore with auth-type gate
  (api_key never aborts; cli/oauth aborts at per-window thresholds);
  rateLimits surfaced on /api/health
- withRetry helper (#2254): honors ClassifiedProviderError.kind, exponential
  backoff with jitter, request-id capture for dedup logging

Bug fixes also landing in 12.6.0:
#2188 stdin fallback, #2196 ANTHROPIC_BASE_URL docs, #2220 chroma CPU storm,
#2225 opencode _zod.def crash, #2231 SECURITY.md, #2233 parser fence (Part A),
#2236 observer visible windows, #2237/#2238 hardcoded paths, #2240 Chroma
dedupe, #2242 check-pending-queue endpoints, #2243 scripts/package.json,
#2244 summaryStored=null, #2247 Codex task_complete, #2248 Cursor sessions,
#2250 health uptime ms, #2253 chroma macOS CPU.

Tests: 1454 pass / 77 fail (matches main baseline, zero net regressions).
All CI green: build, CodeRabbit (17 rounds resolved), Greptile (clean).

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

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

.claude-plugin/marketplace.json

@@ -10,7 +10,7 @@
   "plugins": [
     {
       "name": "claude-mem",
-      "version": "12.5.1",
+      "version": "12.6.0",
       "source": "./plugin",
       "description": "Persistent memory system for Claude Code - context compression across sessions"
     }