The hash becomes the single serialized view (snippet / Datasets list / a dataset
/ new-dataset form / Chart Builder). url-hash is the sole reader/writer of
location+history (total, never-throwing parse; hash-only canonical URLs).
UrlStateSync grows from the modal↔URL seam into the full router: state→hash is
derived from the stores (so in-modal dataset sub-views reach the hash), hash→state
restores on load and on Back/Forward, validating ids and cleaning stale links.
startRouting() runs after store hydrate.
A persistent left-rail toolbar (APG toolbar + roving tabindex) toggles the
library / editor / preview panes; a hidden pane frees its space and the rest
redistribute proportionally to their remembered widths. Visibility persists to
astrolabe:ux-prefs (separate key from widths, so a hidden pane keeps its width).
Adds the positional pane-* glyph sub-family to Icon and a Datasets shortcut
button in the strip.
Portable summarizer (clamped fraction, ok/warning/critical level, availability
flag, humanizeBytes) with the browser StorageManager.estimate() feature-detect
isolated to the infrastructure adapter. No UI consumer yet — core-first per the
AI developer protocol; the Storage Monitor panel (spec §02) wires to it next.