Redesign the explorer in Canopy, the Twigpine theme - #14

The explorer still carried the black gitlawb identity: Geist Mono for
every word, pill controls, and a layer of effect components (globe,
orbit, beams, aurora text, confetti). It now uses the same system as
twigpine.com.

Design
- Canopy tokens: paper, one ink at a few opacities, and the needle,
  which marks only the newest row of a ledger and the Live dot.
- Geist for the interface, Geist Mono for hashes, DIDs, refs, paths and
  commands. Radius 0, 2px on controls. No shadows, blur or gradients.
- Pine mark and the "twigpine / explorer" lockup; new favicon and share
  images; the per-repository share card is redrawn with Geist.
- Overview opens on the claim and a live ledger of ref updates.
- Certificates open as signed documents with every field in full, and a
  verify command that is ready to paste (owner/name and the full id).
- Events, tasks, peers and network nodes are ruled tables. The network
  page drops the globe for a node table with an "updates behind" bar
  and a one-ink replication matrix.
- Status is said in words; only a failure takes a colour.

Behaviour
- Theme follows the OS until the reader picks one. The choice moves to
  a new storage key because the old hook stored "light" on every visit.
- Click a short hash or DID to copy the full value.
- g then a letter jumps between sections; the palette lists all eight.
- Exact timestamps on hover; table roles for the div-based tables.

Removed
- 38 effect components and the packages only they used (gsap, cobe,
  canvas-confetti, tailwind-variants, next-themes,
  class-variance-authority, three unused Radix packages).

Copy
- gitlawb becomes Twigpine in prose. Protocol and client identifiers
  are unchanged: gitlawb://, gl, git-remote-gitlawb,
  gitlawb/ref-updates/v1, did:gitlawb, @gitlawb/gl, GITLAWB_*.