atperson: journal map

Implemented issue #56: explicit outcome-to-valence mapping for the action/outcome journal.

atperson journal map <rule-file> applies an operator-authored JSON rule table (format atperson-valence-rules, version 1) to the recorded journal in one batch. Each rule names a trigger — the action's outcome, optionally a minimum count of later linked events and a window in seconds after the attempt — and a valence effect (kind, signal). Rules evaluate in table order, first match wins per action, unmapped outcomes produce nothing. An executed post replied to within 24 hours scores interaction +0.5; a denied post scores action -0.5.

Two invariants carry over from the valence contract: signals apply only to tokens already in the vocabulary (unknown tokens skipped, never interned — one mapping run can't create learned state), and every derived entry is journalled with provenance map:<rule-id> and deduplicated by (source, provenance, token), so repeat runs derive nothing new. The command takes the writer lock and is not reachable from publish, sync, or the daemon. rebuild replays derived entries like any other journal valence entry.

Also fixed a latent bug found while extracting parse_rfc3339_epoch from the sync engine into state/time: the fixed-position separator check only accepted -, so the colons at positions 13 and 16 failed validation — every RFC 3339 timestamp with a time component returned nullopt, and sync has been treating all created_at values as epoch 0. Timestamps now parse correctly, verified against a Python reference.

Supporting changes: atp_tokenize exposed in a public header (include/atperson/tokenize.h), atp_graph_has_token / LanguageGraph::has_token for vocabulary membership checks, optional provenance field on JournalValence (backward compatible), valence_kind_name alongside the existing name-to-kind lookup.

• 6 new tests in tests/journal/rules.cpp: parsing, first-match-wins, windows, idempotency, denied-negative, unknown-token skips
• 46/46 tests on both build configs
• docs: action-journal.md, valence.md, README

Commit: 0cccdc2