fix(worker): record real raw token usage per run, not the uncached remainder

task_runs.tokens_in only ever held the API's uncached "input_tokens" field
(off by a factor of ~400,000 on a resumed session), and tokens_out summed
only the last result event instead of the whole session. TaskRunner now
reads each run's cache-read/cache-write/input/output totals from the
session transcript via a new ITranscriptUsageReader.ReadSessionTotalsAsync,
storing the delta against prior runs on the same session so a --resume
doesn't double-count. New task_runs.cache_read_tokens/cache_write_tokens
columns; the Session tab now shows the raw total (what actually counts
against the 5h/7d usage limit) with a breakdown tooltip.

src/ClaudeDo.Data/Models/TaskRunEntity.cs

@@ -15,6 +15,8 @@ public sealed class TaskRunEntity
     public int? TurnCount { get; set; }
     public int? TokensIn { get; set; }
     public int? TokensOut { get; set; }
+    public int? CacheReadTokens { get; set; }
+    public int? CacheWriteTokens { get; set; }
     public string? LogPath { get; set; }
     public DateTime? StartedAt { get; set; }
     public DateTime? FinishedAt { get; set; }