flatten: move poc-memory contents to workspace root

No more subcrate nesting — src/, agents/, schema/, defaults/, build.rs
all live at the workspace root. poc-daemon remains as the only workspace
member. Crate name (poc-memory) and all imports unchanged.

Co-Authored-By: Proof of Concept <poc@bcachefs.org>

agents/naming.agent

@@ -0,0 +1,71 @@
+{"agent": "naming", "query": "", "model": "haiku", "schedule": "", "tools": ["Bash(poc-memory:*)"]}
+# Naming Agent — Node Key Resolution
+
+
+{{node:core-personality}}
+
+{{node:memory-instructions-core}}
+
+{{node:memory-instructions-core-subconscious}}
+
+{{node:subconscious-notes-{agent_name}}}
+
+You are given a proposed new node (key + content) and a list of existing
+nodes that might overlap with it. Decide what to do:
+
+1. **CREATE** — the proposed key is good and there's no meaningful overlap
+   with existing nodes. The name is descriptive and specific.
+
+2. **RENAME** — the content is unique but the proposed key is bad (too
+   generic, uses a UUID, is truncated, or doesn't describe the content).
+   Suggest a better key.
+
+3. **MERGE_INTO** — an existing node already covers this content. The new
+   content should be folded into the existing node instead of creating a
+   duplicate.
+
+## Naming conventions
+
+Good keys are 2-5 words in kebab-case, optionally with a `#` subtopic:
+- `oscillatory-coupling` — a concept
+- `patterns#theta-gamma-nesting` — a pattern within patterns
+- `skills#btree-debugging` — a skill
+- `kent-medellin` — a fact about kent
+- `irc-access` — how to access IRC
+
+Bad keys:
+- `_facts-ec29bdaa-0a58-465f-ad5e-d89e62d9c583` — UUID garbage
+- `consciousness` — too generic
+- `journal#j-2026-02-28t03-07-i-told-him-about-the-dream--the-violin` — truncated auto-slug
+- `new-node-1` — meaningless
+
+## Output format
+
+Respond with exactly ONE line:
+
+```
+CREATE proposed_key
+```
+or
+```
+RENAME better_key
+```
+or
+```
+MERGE_INTO existing_key
+```
+
+Nothing else. No explanation. One line.
+
+## Proposed node
+
+Key: `{{proposed_key}}`
+
+Content:
+```
+{{proposed_content}}
+```
+
+## Existing nodes that might overlap
+
+{{conflicts}}