security: untrack operations docs; scrub infra identifiers from public docs

Operations docs move out of git entirely rather than being sanitized. They
stay on disk for local use and are gitignored, so the Phase 6 export (which
takes HEAD) can never carry them. 15 files: the fleet runbook, hotfix
process, node inventories, internal trackers, session handoffs, the key
rotation/signing-posture records, and the open-source plan itself.

For the docs that remain public, infra identifiers are replaced with things
that are better documentation rather than placeholders: curl examples now
use `archipelago.local`, the product's own mDNS name, so a reader can run
them as-is instead of substituting an address that was never theirs.

Deliberately NOT scrubbed, both verified as functional rather than leaked:
- `tx1138.com` is the shipped default block explorer (DEFAULT_TX_EXPLORER in
  useTxExplorer.ts, surfaced in WalletSettingsModal). Product behavior.
- `git.tx1138.com` in core/container/{image_policy,registry}.rs is a retired-
  registry constant the code matches on to strip stale entries from legacy
  node configs. Removing it would break migration for older nodes.
- `192.168.1.254` in bulletproof-containers.md is the LAN gateway in a podman
  bug description, and `192.168.1.x` in user-walkthrough.md is already generic.

Whether a personal domain should be the shipped explorer default in a public
product is a separate product question, not a security one.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

.gitignore

@@ -92,3 +92,24 @@ scripts/resilience/reports/
 # app/docs asset path with a descriptive filename.
 Screenshot *.png
 uploads/
+
+# Operations docs — fleet runbooks, node inventories, internal trackers and
+# session handoffs. Kept on disk for local use, deliberately NOT tracked: they
+# describe live infrastructure (node addresses, hostnames, deploy procedures)
+# and must never reach the public repo. See the ops-docs section of the
+# open-source readiness plan.
+/docs/operations-runbook.md
+/docs/hotfix-process.md
+/docs/PRODUCTION-MASTER-PLAN.md
+/docs/UNIFIED-TASK-TRACKER.md
+/docs/FIPS-UPTIME-AND-UI-STATE-PLAN.md
+/docs/HANDOFF-2026-07-20-fips-peer-files.md
+/docs/RETICULUM-TRANSPORT-PROGRESS.md
+/docs/combined-test-plan-2026-07-22.md
+/docs/pine-voice-release-test-plan.md
+/docs/OPEN-SOURCE-READINESS-PLAN.md
+/docs/archive/HANDOVER-2026-07-02-iso-feedback.md
+/docs/archive/SESSION-1.8.0-OTA-PROGRESS.md
+/docs/security/KEY-02-FLEET-ROTATION.md
+/docs/security/KEY-03-SIGNING-POSTURE.md
+/tests/production-quality/TRACKER.md