docs: fix documentation inconsistencies (issue #291)

- Fix pact-system-spec.md §5.2: Remove misquote of AGENTS.md (pacts do NOT persist)
- Fix pact-system-spec.md §4.2: Update pactBinding note (now resolved in code)
- Fix pact-system-spec.md §8.2/8.3: Correct floor 140/150/200 element tags
- Add pactInterferenceMitigation to AGENTS.md and GAME_BRIEFING.md (15 upgrades)
- Fix GAME_BRIEFING.md §7: Correct Tier 1 armor values and pact times
- Fix GAME_BRIEFING.md §7: Correct Tier 2 armor values and pact times
- Fix GAME_BRIEFING.md §7: Correct Tier 3 pact times
- Fix GAME_BRIEFING.md §7: Correct floor 100 element (sand, not sand+fire+earth)
- Fix AGENTS.md: Update equipment count from 50 to 43
- Fix AGENTS.md: Fix enchantment design time (per stack, not per effect slot)
- Fix GAME_BRIEFING.md §6: Clarify puzzle room frequency (guaranteed per 7th floor)
- Fix GAME_BRIEFING.md §11: Clarify spireKey formula (1 + level × 2)

docs/dependency-graph.json

@@ -1,6 +1,6 @@
 {
   "_meta": {
-    "generated": "2026-06-07T12:41:52.654Z",
+    "generated": "2026-06-07T12:48:15.677Z",
     "description": "Import dependency graph for src/lib/game. Keys are files, values are arrays of files they import.",
     "usage": "To find what a file affects, search for its path in the VALUES. To find what a file depends on, look at its KEY entry."
   },