Backend: new ContractProgress parses the streamed summary JSON and
advances only when contract units finish — first token 5%, each closed
key 5→90 (arrays step per closed item), root close 95, stored=100.
Replaces the char-count ticker that counted reasoning chars against a
guessed 1200-char output and sat frozen at 99 for minutes. No timers,
no elapsed-time estimates; the unfinishable thinking span honestly
earns only the alive-tick. Both adapters (openai_compat, ollama) feed
the accumulated content prefix. /jobs now carries the job's tone.
App: summarize progress shows a real percentage + determinate bar with
the tone named ('Summarizing dry wit… 47% · 1:12') in both detail
widgets; indeterminate only while queued or pre-first-token.
Tests: milestone sequence verified identical for char-by-char and
chunked streaming; adapter thinking-phase test updated to the new
contract (83 passed).
