Session usage limit hit multiple times, burning cash, while finishing less than previously

Bug Description
Using Fable to review some legacy source, it starts a workflow and uses Sonnet for the sub tasks.
After some time it hits the session limit, partially done. I add 50 USD budget and let it continue the session.
It starts to replay the already finished tasks and burns the 50 USD even before finishing to replay.
Given the attached usage statistics this seems odd.

<img width="481" height="504" alt="Image" src="https://github.com/user-attachments/assets/f841667d-474d-4c68-8c6f-5c250e0aca9c" />

Partial session output:

Run 2 got much further: 149 candidates, 115 verified, 107 confirmed, 8 refuted — but it hit the spend limit again near the end (~34 verifiers) and two finder agents died on a socket error. Resuming

Run 3 now has less findings verified from cache that the previous run. 
Map     11/11
Review  21/21
Verify 42/161

Given that I increased the spend limit by 50 USD, I expected to see more findings verified, not less.

**Environment Info**
- Platform: darwin
- Terminal: iTerm.app
- Version: 2.1.170
- Feedback ID: 322179df-b10f-4262-9aad-eca531b3fee1

Errors

[]

❯ /feedback
  ⎿  Feedback / bug report submitted

❯ /stats

────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
  Settings  Status   Config   Usage   Stats

   Overview   Models


  Tokens per Day
    2.9M ┼               ╭───────╮
    2.6M ┼───────╮       │       │
    2.2M ┤       │       │       ╰───────╮       ╭───────
    1.8M ┤       │       │               │       │
    1.5M ┤       │       │               ╰───────╯
    1.1M ┤       │       │
    730k ┤       │       │
    365k ┤       ╰───────╯                       ╭───────
       0 ┼───────────────────────────────────────────────
          Jun 5         Jun 6         Jun 8         Jun 10
  ● Opus 4.8 · ● Fable 5 · ● Sonnet 4.6

  All time · Last 7 days · Last 30 days

  ● Opus 4.8 (96.1%)                      ● Sonnet 4.6 (1.7%)
    In: 1.4m · Out: 10.7m                   In: 5.1k · Out: 202.2k
  ● Fable 5 (2.2%)
    In: 80.5k · Out: 198.8k

    ↑ tabs · r to cycle dates · ctrl+s to copy