release(v1.12.0): pi 1.3.0, mempalace 3.11.0, pi-atelier v0.16.0

Every component at its newest upstream release; each pinned one audited
against this image before tagging, none breaking.

- ARG PI_VERSION 1.2.0 -> 1.3.0. No breaking-changes section. pi-agent-core,
  pi-tui and dist/core/extensions are byte-identical to 1.2.0. The only
  removed export (parseModelPattern, not index-exported) and pi-ai's dropped
  assistant-message-frame re-export have 0 consumers; all 54 runtime-imported
  names across the stack and /opt/fleet-pi resolve (negative control
  reported). With a copy of tor-ms22's ~/.pi/agent: pi -p exits 0 in 10 s,
  all extensions load, bridge 45 tools, /om:* and /studio offered, atelier
  paints in both renderers (-ne controls: none).
- ARG MEMPALACE_VERSION 3.10.0 -> 3.11.0. init --yes still writes
  config.json; a 3.10.0-built palace opens, searches and serves MCP under
  3.11.0, re-mines its convo file once, then skips it; stdio MCP 45 -> 47
  tools, none removed. research() removal: 0 callers. synlig hub stays
  3.10.0 (newer-client direction); upgrade notes in CHANGELOG.
- ARG PI_ATELIER_REF/VERSION v0.15.0 -> v0.16.0 (3b42825). Additive
  (keyValues rows, progress bars, two roles, meter background). Protocol
  and pi floor unchanged; fleet:todos panel renders a real todo on both
  versions; the meter-background escape tells the two arms apart.
- Base rebuilds anyway, so BASE_REBUILD_DATE marker refreshed (uv 0.13.1,
  gitea-mcp 1.9.0, Node 24.22.0 re-resolve).
- CHANGELOG: Unreleased -> v1.12.0 — 2026-10-18. README pin table (and
  "Three" -> "Four" components), sanity-check example; DOCKER_HUB.md's stale
  "29 mempalace_* tools".

Local gates: check-doc-drift rc 0 (check 9 names pi, mempalace, atelier,
pi-extensions), lint-shell, check-workflow-shell, test-link-pi-models
13/13, test-link-pi-extensions 16/16, directive guard, skill floor.

Dockerfile.base

@@ -14,7 +14,7 @@
 # content-addressed over this file, so any byte change invalidates the
 # cache. Recommended cadence: once per release for security updates.
 #
-# BASE_REBUILD_DATE: 2026-10-14 (v1.11.1 — rootfs skill floor to pi-extensions 750b2a8, mempalace-toolkit d5a03f4; apt and base tools re-resolve (upstream unchanged since 2026-10-12: uv 0.13.0, nvim 0.12.6, fzf 0.74.5); previous marker 2026-10-12 / v1.11.0)
+# BASE_REBUILD_DATE: 2026-10-18 (v1.12.0 — mempalace 3.11.0, link-pi-extensions.sh, studio-expose and skill doc fixes; apt and base tools re-resolve (upstream on 2026-10-18: uv 0.13.1, gitea-mcp 1.9.0, Node v24.22.0; nvim 0.12.6, fzf 0.74.5 unchanged); previous marker 2026-10-14 / v1.11.1)
 #
 # ── Lineage note ─────────────────────────────────────────────────────
 # Adapted from opencode-devbox/Dockerfile.base (commit before v1.16.2).
@@ -639,7 +639,30 @@ ARG INSTALL_MEMPALACE=true
 # positive control logged one). So 3.10.0's new CLI write-routing policy never
 # runs against the hub from this image; the client pin touches first-run
 # `mempalace init` and the on-disk layout, nothing else in remote mode.
-ARG MEMPALACE_VERSION=3.10.0
+#
+# v1.12.0: 3.10.0 -> 3.11.0 (PyPI 2026-10-14). Core requirements unchanged.
+# Three "Upgrade notes", checked against our callers and measured with both
+# wheels in throwaway uv venvs and a throwaway palace:
+#   - `EntityRegistry.research()` / `confirm_research()` removed: 0 callers in
+#     pi-devbox, mempalace-toolkit, skillset or myconfigs.
+#   - The first conversation mine re-mines each covered conversation file once
+#     (the exchange chunker stopped discarding text). LOCAL palaces only from
+#     this image: in remote mode the hub does the mining. Measured: a palace
+#     built by 3.10.0 (84 drawers) re-mined its one convo file under 3.11.0
+#     (83 -> 84 drawers, old ones replaced, 2 s); the next mine skipped it.
+#   - A palace refuses to open with a different embedder than the one that
+#     built it. The default (MiniLM) is unchanged and nothing here sets
+#     `embedding_model`; the 3.10.0-built palace opened, searched and served
+#     MCP under 3.11.0 with no warning.
+# `mempalace init --yes` (entrypoint) still writes config.json, rc 0. MCP over
+# stdio: 45 -> 47 tools, none removed or renamed (+delete_drawers,
+# +get_drawers); 14 read-only tools now carry `readOnlyHint`. Skew: synlig's
+# hub is still 3.10.0 (measured 2026-10-18), the newer-client direction, and
+# the bridge's tool list comes from the hub, so nothing changes for shared-
+# palace devices until synlig upgrades. When it does, ITS first convo mine
+# re-mines every inbox transcript still on disk (upstream: 40 min to 3 h per
+# million drawers); back it up and run it at a quiet time.
+ARG MEMPALACE_VERSION=3.11.0
 # Recorded as a label HERE, not in Dockerfile.variant, for three reasons: the
 # value lives next to the ARG that defines it (a second copy in the variant
 # would be one more pin able to drift, which is the class check-doc-drift.sh