Rollback adaptive DRC portfolio continuation

[imrishabh18]

Summary

• revert the broad-branch continuation introduced in this PR
• restore the original portfolio order and accepted-output behavior
• remove the direct high-count trace/via candidate after it changed unrelated boards

Why

The continuation reduced Bug94 from 6 to 2 DRC errors, but it was an adaptive second broad pass. SRJ18 completion dropped by 6.3 percentage points: sample 1 lost its DRC pass and two vias, while sample 2 timed out. The direct trace/via alternative also produced large unrelated snapshot deltas.

The final branch is intentionally net-equivalent to current main; the commit history documents and removes the regressing approach. No feature flags, sample thresholds, or adaptive solver calibrations remain.

Validation

• CI test, typecheck, and formatcheck pass
• SRJ18 sample 1: DRC pass, 184 vias
• SRJ18 sample 2: solved in 144.6s, no timeout
• Bug94 returns to the non-adaptive 6-error result with 232 vias

[tscircuitbot]

Benchmark This PR

Run benchmarks by commenting on this PR:

/benchmark [benchmark.sh args...]
/benchmark [scenario-limit|all] --dataset <drc14|srj18> --concurrency <n> --effort <n> --max-iterations <n>

Everything after /benchmark is forwarded directly to ./benchmark.sh.

Examples:

• /benchmark -> run default SRJ18 benchmark settings
• /benchmark 10 -> run first 10 SRJ18 samples
• /benchmark --dataset srj18 -> run all SRJ18 samples
• /benchmark 1 --dataset srj18 -> run the first SRJ18 sample
• /benchmark --dataset drc14 -> run all DRC14 samples
• /benchmark all --concurrency 4 -> run all SRJ18 samples with 4 workers
• /benchmark --scenario-limit all --effort 2 -> run all samples with effort 2
• /benchmark --scenario-limit 20 --max-iterations 100 -> run 20 samples with a max iteration override

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