report.ts: effectiveCompressedTokens carries two unused legacy params, forcing placeholder args at 7 call sites

[ranxianglei]

Context

v0.0.17, b9f9e99. effectiveCompressedTokens in src/report.ts:23-36 has this signature:

function effectiveCompressedTokens(
    block: CompressionBlock,
    _state: CompressionState,
    _countTokens: (t: string) => number,
): number {
    // block.compressedTokens already records the full input token count ...
    // Recursing into directBlockIds ... double-counts the consumed children,
    // so we return the block's own value directly.
    return block.compressedTokens;
}

Both _state and _countTokens are unused. The body is a single field read: return block.compressedTokens;.

Why it matters

Because of the wide signature, every one of the 7 call sites (src/report.ts:173, 184, 185, 190, 286, 287, 293, 306) has to thread state and countTokens through:

effectiveCompressedTokens(b, state, countTokens)   // repeated 8x

…even though those values are never used inside. It clutters the report code and makes a reader think the function does something stateful/token-aware (it does not).

The leading-underscore params + the comment explain why the recursion was removed, but they do not explain why the signature was kept wide. My guess: preserved for a possible future re-introduction of recursion. If so, that intent is worth a one-line comment; if not, the signature should narrow.

Suggested fix

Either:

• (preferred) Narrow the signature to (block: CompressionBlock): number and simplify all 8 call sites to effectiveCompressedTokens(b) — or just inline b.compressedTokens at each site, since it is a single field read.
• (minimal) Keep the signature, add a comment stating "signature retained so a future tier-aware recursion can be reintroduced without touching call sites" so the next reader is not puzzled.

Severity

Low — readability/maintenance only. No behavioral impact.