refactor(tr): Phase 1 - add ONLY clauses to USE TRCOMM (4 files)

[k-yoshimi]

Summary

Phase 1 of the TR module refactoring per docs/superpowers/specs/2026-04-17-tr-refactoring-design.md section 5.

Each USE TRCOMM (no ONLY clause) in the four target files now lists only the symbols actually referenced in that scope.

Files modified

• tr/trloop.f90 — tr_loop (1 USE site, 21 symbols)
• tr/trfout.f90 — tr_fout (1 USE site, ~40 symbols)
• tr/trparm.f90 — tr_parm + tr_nlin (2 USE sites; tr_nlin lists full namelist)
• tr/trrslt.f90 — TRGLOB + TRPRNT + tr_setup_kv (3 USE sites)

No other files modified. No semantic changes.

Behavior invariance

Verified by direct pre/post regression comparison on tr_m0904:

• Pre-Phase-1 metrics (original code, this build environment) → snapshot
• Post-Phase-1 metrics (this PR's code, same build environment) → compared
• Result: OK: metrics match within tol=1e-10 ✅

Note: The Phase 0 regression baseline (test_run/baselines/) was generated in a different build environment and shows pre-existing drift from develop's HEAD (~1e-5 to 1e-3) independent of this PR. That baseline mismatch and a pre-existing libc abort at exit time are out of scope for this PR.

Test plan

• gfortran -O3 -m64 -std=legacy compile clean
• tr2 binary built successfully
• tr_m0904 (analytic-geometry test, no eq dependency) runs to CLOSED
• Pre/post metrics.json direct comparison passes within 1e-10
• tr_iter01 / tr_tst2: skipped (require eq build, not present in this env)

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Note

Low Risk
Low risk refactor limited to USE TRCOMM import lists; main risk is accidental omission of a needed symbol causing compile/runtime issues, but behavior should be unchanged.

Overview
Refactors four TR Fortran sources to replace broad USE TRCOMM statements with explicit ONLY symbol lists in key routines (tr_fout, tr_loop, tr_parm/tr_nlin, TRGLOB/TRPRNT/tr_setup_kv).

This narrows module dependencies and makes each routine’s TRCOMM usage explicit, without intended semantic changes.

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[k-yoshimi]

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[k-yoshimi]

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