Previously a cross-wing topic tunnel for "Angular" stored the room as
"Angular" — colliding with a wing's literal folder-derived "Angular" room
at follow_tunnels/list_tunnels read time, and exposing raw topic strings
(which may contain characters rejected by sanitize_name) to the MCP
surface.
Topic tunnels now store their room as "topic:<original-casing>" and carry
kind="topic" on the stored dict. Explicit tunnels get kind="explicit"
(default). follow_tunnels("wing", "Angular") on a literal Angular room
no longer surfaces topic connections for the same name, and any LLM
scanning list_tunnels has a visible discriminator.
When two wings have one or more confirmed TOPIC labels in common, the
miner now drops a symmetric tunnel between them at mine time so the
palace graph reflects shared themes (frameworks, vendors, recurring
concepts).
- llm_refine: TOPIC label routes to a dedicated `topics` bucket so the
signal survives confirmation instead of getting collapsed into
`uncertain` and dropped.
- entity_detector / project_scanner: bucket plumbed through the
detection pipeline; `confirm_entities` returns confirmed topics
alongside people/projects.
- miner.add_to_known_entities: optional `wing` parameter records the
confirmed topics under `topics_by_wing` in
`~/.mempalace/known_entities.json`. Wing names do NOT leak into the
flat known-name set used by drawer-tagging.
- palace_graph: `compute_topic_tunnels` and `topic_tunnels_for_wing`
create symmetric tunnels via the existing `create_tunnel` API so they
share dedup and persistence with explicit tunnels.
- miner.mine: post-file-loop pass calls `topic_tunnels_for_wing` for
the freshly-mined wing. Failures are logged but never abort the mine.
- config: `topic_tunnel_min_count` knob (env
`MEMPALACE_TOPIC_TUNNEL_MIN_COUNT` or `~/.mempalace/config.json`),
default 1.
Tests cover topic persistence through init->mine, tunnel creation when
wings share a topic, no tunnel below threshold, cross-wing tunnel
retrieval via `list_tunnels`, dedup on recompute, case-insensitive
overlap, and the end-to-end mine-time wiring.
Out of scope for this PR (called out in the PR body): manifest-
dependency overlap, per-topic allow/deny lists, search-result surfacing.
~/.mempalace/tunnels.json (introduced in #790) was created via plain
open(..., "w") with no chmod, and its parent dir via os.makedirs()
without mode=0o700. On Linux with default umask 022 both end up
world-readable (0o644 / 0o755).
Tunnels reveal cross-wing connections — which projects, people, and
rooms the user has explicitly linked — so they are sensitive metadata
that should not be readable by other local users on shared systems.
Apply the same 0o700 / 0o600 pattern that #814 established for the
other sensitive palace files. Chmod calls are wrapped in try/except
(OSError, NotImplementedError) for Windows / unsupported-filesystem
compatibility.
Closes#1165