Triage a dermestes finding

Each finding is a deletion candidate: an abstraction with a single user, or none.

const-param src/db.py:209 insert_history
  calls: 2 prod, 0 test
  duration_s: default None never overridden
  suggest: drop duration_s, use None inline
pass-through src/entries.py:474 resolve_relation
  form: forward → src/entries.py:459 resolve_entry; calls: 1 prod, 0 test
  suggest: call resolve_entry directly at src/entries.py:492, delete resolve_relation
dead-code src/report.py:543 _fetch_cost_rows
  calls: 0 prod, 2 test
  tests: tests/test_report.py:30, tests/test_report.py:41
  suggest: delete _fetch_cost_rows and the tests that only exercise it, or move it into tests/test_report.py if they use it as setup

The first line is the check id and the definition; indented lines are the evidence and the fix. one-impl names the single implementation of an ABC or Protocol (maybe structural). const-param has a line per parameter: always <value>, or passed explicitly at N sites when callers write the default. pass-through forms: forward only calls a repo function, binding at most short literals or one constant; rename renames an outside call for 2 callers; single-use is a private one-liner with one call. dead-code: no production code mentions the name; tests: lists the test lines that do.

For each finding:

1. Read the evidence. Is it a deliberate seam the counts cannot see (a plugin point, a public API, a knob a caller outside the repo turns)?
2. If not, apply the suggest: line, then run the tests.
   • const-param: remove the parameter, use the value in the body, delete every branch the value makes dead, then update the calls.
   • pass-through: replace each listed call with the call the suggestion writes (forward, rename) or the body (single-use), then delete it.
   • dead-code: delete it; delete or rewrite the listed tests with it.
3. If it is deliberate, suppress it with a reason on any line of its header (a decorator through the closing :): # dermestes: keep <reason>. Without a reason it still reports, with a keep: missing reason line.

Known misses (it stays silent, by design):

• one-impl: a test implementation, an unresolvable base or subclass, or a plain base class (no ABC, no abstract methods) with one subclass.
• Calls count only when resolved (f(), mod.f(), self.m(), Class()); one on a variable (tr.done()) that could bind silences the counters.
• All are silent for functions used as values, decorated ones, overrides, overridden methods, methods of a class with a third-party base.
• const-param: a variable or enum member is never “the same value”.
• pass-through: any test caller vetoes it, as do a third-party target for a forward, a public wrapper of a private one, *args, a multi-statement body.
• dead-code: callers that are themselves dead, a name only in prose or __all__, one shared with another method, public names in a py.typed package.
• Syntax-error files are skipped. Diff mode ignores untracked files: git add -N.

dermestes guide tune lists the config keys that exempt whole paths.

next: run dermestes