feat(glossary): add optional paths.glossary standing-reading slot

Pins canonical nomenclature per project so terminology does not drift
and LLM-driven work reuses the established term instead of coining a
synonym each session. The glossary rides the existing standing-reading
mechanism — one optional path slot, no new delivery path.

Single-sourcing, to avoid cross-doc drift:
- `paths.glossary` row in profile-schema.md owns the "set => standing
  reading for every role; unset => no-op" semantics; agent-template.md
  and pipeline.md each carry one referencing sentence, not a restatement.
- glossary-convention.md owns the format (flat per-term blocks: canonical
  heading + Avoid line + <=2-sentence definition) and the boss
  record-reality-never-invent write-rule; boss/SKILL.md only points to it.
- glossary.md dogfoods the format on the plugin's own vocabulary
  (cycle, milestone, iteration, drift, hard-gate).

Write authority: user any time; boss autonomously but only to record
terms already in consistent use or to settle a drift it just resolved —
never to coin. All other roles are read-only consumers.

No executable surface; this repo has no test runner, so each task closed
on a grep presence-assertion against the file it touched. All eight gates
green (T1 3>=3, T2 5, T3 2, T4 1, T5 1, T6 1, T7 2, final sweep present).

Implements docs/specs/2026-05-31-glossary-integration-design.md.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs/glossary-convention.md

@@ -0,0 +1,59 @@
+# Glossary convention
+
+A project's glossary pins canonical nomenclature so terminology does
+not drift over time, and so that LLM-driven work reuses the
+established term for a concept instead of coining a fresh synonym each
+session. This file owns the format, the reading obligation, and the
+write discipline; an individual project's glossary is an instance of
+this convention.
+
+## Where it lives
+
+A project opts in by setting `paths.glossary` in its
+`.claude/dev-cycle-profile.yml` (see `profile-schema.md` § `paths`).
+When the slot is set, the file it names is standing reading for every
+role — no separate `standing_reading.always` entry is required. When
+the slot is unset, the whole feature is a documented no-op.
+
+## Format
+
+The glossary is a flat list of per-term blocks (not a table), so an
+appended entry produces a clean line-wise diff. Each block has exactly
+three fields:
+
+1. a level-3 heading naming the **canonical term** to use;
+2. an **Avoid:** line listing known synonyms that must NOT be used;
+3. a definition of at most two sentences.
+
+```
+### canonical-term
+**Avoid:** synonym-one, synonym-two
+A definition of at most two sentences.
+```
+
+A term with no known synonyms still carries an `**Avoid:** —` line so
+every block has the same three-field shape.
+
+## Reading obligation
+
+Every skill and agent reads the glossary as part of its standing
+reading and, when producing prose or naming a concept, uses the
+canonical term and avoids the listed synonyms. If a concept is not
+listed, reuse the closest existing term — do not silently coin a new
+one.
+
+## Extending the glossary (user + boss only)
+
+The user may edit the glossary at any time. In a `/boss` session the
+orchestrator may extend it autonomously — but only to **record
+reality, never to invent**:
+
+- A term already used consistently across shipped artefacts but not
+  yet listed → add it, with its known synonyms under **Avoid**.
+- A drift the orchestrator just resolved (two terms for one concept)
+  → record the winner as the canonical entry, the loser under
+  **Avoid**.
+
+The orchestrator never coins a brand-new term into the glossary: a
+term earns its entry by already being in consistent use. All other
+skills and agents are read-only consumers of the glossary.