feat(knowledge): rebuild the project notes panel as Project knowledge (#2973)

The panel stored notes, todos and plans inside one shared JSON file that
six unrelated domains also wrote to, synchronised itself through window
CustomEvents, and could only read plans. It is now Project knowledge:
server-owned storage with explicit routes, a store with rollback, a
section sidebar, plans that open and edit in place, and search across
all of it.

Notes and plans the user pins travel with every message sent in that
project. Pinning is project state, not an attachment to one message, so
it holds until unpinned and the work status panel names what is riding
along and can detach it.

Agent memory is added alongside, in two scopes: what is true about the
user, and what is true about this codebase. The split is not cosmetic —
a wrong project fact costs one project and is noticed, while a wrong
global fact quietly shapes every session everywhere and the user has no
code to check it against. It stays separate from notes so an agent
mistake cannot land in what the user wrote. Sessions receive an index of
titles only; bodies are read on demand, because an index carrying full
text grows until it crowds out the conversation.

Deciding what a session must be told, and whether it has been told, now
lives on the server. The client owned it before, which meant sessions
started without a UI — scheduled tasks, sessions the agent dispatches —
received nothing at all, and a tab's record of what it had sent outlived
the conversation: after compaction the agent no longer held the block
while the tab went on believing it did. What was delivered is recorded
in the session's own metadata, and compaction restores it through the
runtime that already restores pinned messages, in the same turn.

Agent memory ships dark behind OPENCHAMBER_MEMORY_ENABLE: unset, there
is no tool, no routes, no session index, no settings row and no panel
tab. Absent rather than switched off, so nothing invites turning on a
feature that has not been announced. Pinned notes and plans are
unaffected and ship as normal.

packages/web/server/lib/openchamber-control/actions.js

@@ -53,8 +53,86 @@ export const OPENCHAMBER_WEB_ACTIONS = Object.freeze(
   OPENCHAMBER_WEB_ACTION_DEFINITIONS.map(({ action }) => action),
 );
 
+/**
+ * Memory is its own tool for the same reason web is: remembering across
+ * sessions is a distinct intent from controlling one, and a shared description
+ * would blur both. It also has to switch off cleanly and completely, which a
+ * shared schema cannot do.
+ *
+ * The session already carries an index of stored titles, so the descriptions
+ * push the model toward reading one entry it can already see rather than
+ * listing everything again — and toward reading it at all, since a title that
+ * reads as a complete fact is exactly the one whose conditions get lost.
+ */
+export const OPENCHAMBER_MEMORY_ACTION_DEFINITIONS = Object.freeze([
+  { action: 'memory.read', title: 'Read a stored memory', description: 'Read the full text of one memory listed in the session index. The index shows titles only, and a title omits the conditions that decide how the memory applies, so read before acting rather than working from the title. Requires title (as the index spells it) or memoryId; scope is optional and both stores are searched without it' },
+  { action: 'memory.list', title: 'List stored memories', description: 'List stored memory titles when the session index is missing or stale; scope is global, project, or both (default)' },
+  { action: 'memory.save', title: 'Remember something', description: 'Store a durable fact, preference, or reference; requires title and body, plus scope global (about the user) or project (about this codebase). Restating something already stored updates it. Do not store secrets, one-off task state, or anything the user asked you not to keep' },
+  { action: 'memory.delete', title: 'Forget a memory', description: 'Delete a memory that turned out to be wrong or obsolete; requires memoryId and scope' },
+]);
+
+export const OPENCHAMBER_MEMORY_ACTIONS = Object.freeze(
+  OPENCHAMBER_MEMORY_ACTION_DEFINITIONS.map(({ action }) => action),
+);
+
+/**
+ * Which actions each managed tool may ask for.
+ *
+ * The callback needs this because models routinely drop the namespace: asked
+ * for `memory.read` from a tool already called `openchamber_memory`, they send
+ * `read`, since the tool's own name appears to have said "memory" already. The
+ * name is unambiguous inside one tool's action set even when it is not across
+ * all of them (`delete` belongs to both schedule and memory), so resolution
+ * starts from the tool that asked.
+ */
+const ACTIONS_BY_TOOL = Object.freeze({
+  openchamber: OPENCHAMBER_AGENT_TOOL_ACTIONS,
+  openchamber_web: OPENCHAMBER_WEB_ACTIONS,
+  openchamber_memory: OPENCHAMBER_MEMORY_ACTIONS,
+});
+
+const bareName = (action) => {
+  const separator = action.indexOf('.');
+  return separator === -1 ? action : action.slice(separator + 1);
+};
+
+const uniqueMatch = (candidates, requested) => {
+  const matches = candidates.filter((candidate) => bareName(candidate) === requested);
+  return matches.length === 1 ? matches[0] : null;
+};
+
+/**
+ * The canonical action for what a tool asked, or the reason it could not be
+ * resolved. The reason lists what the tool can actually do: an error that only
+ * says "unsupported" leaves the model to guess again, which is how one wrong
+ * name becomes three.
+ */
+export const resolveAgentToolAction = (requested, toolName) => {
+  const value = typeof requested === 'string' ? requested.trim() : '';
+  const scoped = ACTIONS_BY_TOOL[toolName] ?? null;
+  const known = scoped ?? OPENCHAMBER_ALL_ACTIONS;
+
+  if (value && known.includes(value)) {
+    return { action: value };
+  }
+  if (value) {
+    const resolved = uniqueMatch(known, value)
+      // A tool that did not identify itself still gets the benefit when the
+      // bare name means only one thing across every action.
+      ?? (scoped ? null : uniqueMatch(OPENCHAMBER_ALL_ACTIONS, value));
+    if (resolved) {
+      return { action: resolved };
+    }
+  }
+
+  return {
+    error: `Unsupported OpenChamber action: ${value || 'missing'}. Use one of: ${known.join(', ')}`,
+  };
+};
+
 /** Everything the callback route will dispatch, whichever tool asked. */
 export const OPENCHAMBER_ALL_ACTIONS = Object.freeze([
   ...OPENCHAMBER_CONTROL_ACTIONS,
   ...OPENCHAMBER_WEB_ACTIONS,
+  ...OPENCHAMBER_MEMORY_ACTIONS,
 ]);