release: audited bumps (pi 0.85.1, mempalace 3.9.0, atelier v0.10.1) + two guards

Version audit for the next release. pi 0.84.4 -> 0.85.1, deliberately skipping
0.85.0 (it published internal experimental code and broke SDK imports,
upstream #9132). mempalace 3.8.0 -> 3.9.0. pi-atelier v0.10.0 -> v0.10.1.
PI_STUDIO_VERSION relabelled none -> v0.9.60-rc.0 so the floating main ref's
RC status is visible at docker-inspect time instead of discovered later.
PI_FORK_REF stays floating and adopts e69725c.

The pi bump was verified by running it under a pty in five combinations rather
than by reading the changelog, because this repo has already shipped a version
pair no changelog flagged (atelier < 0.7.1 hangs pi >= 0.84). CPU delta
0.00-0.01s over 5s against a ~5s sustained-CPU hang signature, two-sided via
the atelier sidebar painting identically to the 0.84.4 control.

NODE_VERSION stays 22 on purpose: node 24 is technically safe (pi's five
prebuilt addons are all NAPI, nothing declares a ceiling, agent-browser's
engines.node >=24 is vestigial for the shipped aarch64 ELF), but this release
already moves two minors and bakes an RC, and a node major would leave four
suspects if the image misbehaves. Own release, smoke suite as the gate.

Also corrects a stale claim at the mempalace ARG: synlig serves 3.8.0
server-side, not 3.7.1 (measured over ssh 2026-09-06).

agent-browser volume shadowing: the image has shipped 0.35.2, but every
session on mbp-m1-2020 ran 0.27.0 from a 2026-07-17 hand-install in
~/.pi/npm-global (a VOLUME, at PATH position 2 vs /usr/bin at 8). Third
package hit by this hazard after pi and pi-atelier, so the guard is now
generalised: entrypoint-user.sh retires the copy by moving it aside
(reversible, only when the image ships its own), recreate-sanity-check.sh
asserts resolution under /usr where the volume is real, smoke-test.sh carries
the build-time half and says in the source why it is weak. The real damage was
the stale BUNDLED SKILL (3 skillsets/17.6 KB vs 8/31.5 KB, ten subcommands
undocumented to the agent) - a stale tool errors, a stale skill quietly
teaches wrong commands.

pi-fork capability floor (extensions: []): forks were measured across four
dispatches ignoring their brief, answering in the user's voice, fabricating
self-referential measurements, and once filing a diary entry as agent_name=pi.
Cause is upstream by design - the child gets getHeader()+getBranch(), the
whole active session branch, with the brief as the final user message. Not a
model-capability problem: the same model as the fast profile obeyed the
identical brief perfectly with a fresh session and no inherited context.
extensions: [] runs children with --no-extensions, so the mempalace bridge is
absent and palace writes are impossible by construction (verified by asking a
child to enumerate its tools: read, bash, edit, write). Removes palace writes,
not filesystem writes.

Dockerfile.base

@@ -450,13 +450,26 @@ ARG INSTALL_MEMPALACE=true
 # the part that should stay manual.
 #
 # Deployment sequencing note for whoever ships this bump: synlig (the shared
-# central palace host) currently serves mempalace 3.7.1 SERVER-SIDE via
-# docker-compose.mempalace.yml, which reuses this same devbox image. Bumping
-# this ARG changes only the CLIENT version baked into pi-devbox images: it
-# introduces client/server skew until synlig's compose stack is separately
-# rebuilt/redeployed with the new pin. Not something to code around here —
-# just sequence the redeploy.
-ARG MEMPALACE_VERSION=3.8.0
+# central palace host) serves mempalace 3.8.0 SERVER-SIDE via
+# docker-compose.mempalace.yml, which reuses this same devbox image. (Measured
+# 2026-09-06 over ssh: synlig's UV_TOOL_DIR mempalace entry last changed
+# 2026-08-25 15:33 — this comment previously said 3.7.1, which was stale.)
+# Bumping this ARG changes only the CLIENT version baked into pi-devbox
+# images: it introduces client/server skew until synlig's compose stack is
+# separately rebuilt/redeployed with the new pin. Not something to code around
+# here — just sequence the redeploy.
+#
+# v1.8.13: 3.8.0 -> 3.9.0. Audited: no Breaking/Removed changelog headings.
+# Adopted mainly for #2281 (`mempalace_mine` accepts a single conversation
+# file again) — though note that does NOT unblock this image's own feeder,
+# which was measured to mine DIRECTORIES, not files, so it was never hitting
+# that bug. Four behaviour changes ride along and are skew-relevant while
+# synlig stays on 3.8.0: hub-forward escaping, an HTTP lock split, similarity
+# score semantics, and parsed-output compatibility. 3.9.0-only features
+# (release awareness, `task create`/`task launch` MCP tools) are SERVER-side,
+# so they stay dark until synlig is redeployed — a client bump alone cannot
+# light them up.
+ARG MEMPALACE_VERSION=3.9.0
 ENV UV_TOOL_DIR=/opt/uv-tools
 ENV UV_TOOL_BIN_DIR=/usr/local/bin
 RUN if [ "${INSTALL_MEMPALACE}" = "true" ]; then \