chore(agent): phase roadmap from TODO.md, 2 phases

Convert the two TODO items into append-mode phases (Protocol B):
18_nav_hamburger (TODO L3) and 19_ups_events_expandable (TODO L4),
numbered after the existing todo phases. TODO.md is cleared to an
empty list; its items now live in .agents/phases/todo/.

LLM-Generated: true

.agents/phases/todo/18_nav_hamburger/01_hamburger_markup.md

@@ -0,0 +1,31 @@
+# Task 01 — The hamburger button markup
+
+**Phase:** `18_nav_hamburger` · **Source:** `TODO.md:3` — "The nav bar needs to collapse into a hamburger like brain of reese does"
+**Story:** n/a
+
+## Objective
+
+The seven pages that carry the tab nav each gain the hamburger button and the `nav` id, so the (later task's) CSS and binding have stable anchors to work on. The markup is identical on every page, and `/login` — which deliberately renders only the brand link and the theme toggle — stays untouched.
+
+## Work
+
+1. `src/dashboards/web/pages/index.html` · `system.html` · `disks.html` · `llm.html` · `ups.html` · `settings.html` · `certs.html` — in each masthead, immediately before `nav class="tabs"`, add the toggle:
+   ```html
+   <button class="ghost nav-toggle" id="nav-toggle" type="button"
+           aria-expanded="false" aria-controls="nav-tabs" aria-label="Toggle navigation">☰</button>
+   ```
+   and give the nav its id: `<nav class="tabs" id="nav-tabs" aria-label="Dashboards">`. The button sits between `.brand` and `nav.tabs`, inside the same `<header class="masthead">` — one element per page, no script changes in this task.
+2. `src/dashboards/web/static/dash.css` — add the one base rule beside the other `button.ghost, a.ghost` family (the masthead section): `.nav-toggle { display: none; }` — the button is invisible on every width until task 02's ≤640px block shows it, so the project stays exactly as it looks today after this task.
+3. `src/dashboards/web/pages/login.html` — **no change.** Verify by `grep -c 'id="nav-toggle"'` returning 0 (the pin lands in task 04).
+4. `ASSUMPTION:` the TODO named brain of reese's behaviour, not its breakpoint or glyph. This task takes the 640px breakpoint (brain's `(max-width: 640px)` and `dash.css`'s existing 640px block) and the `☰` glyph with `aria-label="Toggle navigation"`; the CSS task owns the visual.
+5. `ASSUMPTION:` only the tab nav collapses on phones. The `masthead-right` cluster (`#nav-status` dots, pause, `⚷ Certs`, `⚙ Account`, theme toggle) stays visible; the masthead wraps to two rows at ≤640px (task 02).
+
+## Testing & Quality
+- Integration: the served pages still pass the untouched masthead pins (`test_the_disks_tab_is_in_the_masthead_of_every_page`, `test_every_page_links_to_both_admin_pages`) and the orphan-`id` audit — `#nav-toggle` is referenced by the (task 02) stylesheet rule and `aria-controls`, so the audit must not flag it
+- Coverage: **>90%** on modified code (HTML only — the gate's `node --check` and pytest suite are the checks)
+
+## Completion Criteria
+- [ ] `grep -l 'id="nav-toggle"' src/dashboards/web/pages/*.html` lists exactly the seven tabbed pages, never `login.html`
+- [ ] every one of the seven carries the identical button block and the `nav` id (diff of the blocks across pages is empty)
+- [ ] `uv run pytest -q` green; `bash .agents/validate.sh` green
+- [ ] no behavior change: at every width the pages render exactly as before after this task (the button is `display:none` from the base rule shipped with it)