feat: redesign proposal message bubbles

[ivan-jukic]

Restyle the mobile proposal card with a new header/status layout, inline vote buttons, a details sheet, and an updated voting progress bar. Adds ProposalStatusLabel and a "how a proposal passes" explainer.

[github-actions]

canbench 🏋 (dir: .)

./canbench_results.yml is up to date ✅

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Benchmark: add_reactions
  total:
    instructions: 1.36 B (0.00%) (change within noise threshold)
    heap_increase: 5 pages (no change)
    stable_memory_increase: 0 pages (no change)

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Benchmark: push_simple_text_messages
  total:
    instructions: 207.96 M (0.03%) (change within noise threshold)
    heap_increase: 12 pages (no change)
    stable_memory_increase: 0 pages (no change)

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