[filedyoda]

Step 1 of FIL-4. Adds manifest.json entries (SHA-256) for mef/2026v3.0, mef/2026v4.0, and the 2026v3.0/v4.0 business rules (.xlsm, since the IRS no longer ships CSV), plus matching rows in irs/README.md. Metadata only: no code, no tax values, no baselines changed.

Verified: the hashes were computed from the files installed in irs/. check:irs (run as bun scripts/testing/irs.ts) reports the new packages present and unaltered. It lists 11 of 12 packages present; the gap is the unrelated public ty2026-corpus snapshot.

Not verified: check:mef, check:ats, check:ty2026, structure and unit gates were not run, because the change does not touch code they read. CI skips irs/ content, which is gitignored. Nothing was tested against a live ATS run, which needs Filed's IRS credentials.

Next PRs: v3.0/v4.0 rules conversion, the diff against 2026v1.0, and the builder update.

🤖 Generated with Claude Code

[filedyoda]

Taxo review for FIL-4 step 1: approve. GitHub won't record a formal approval, because the agent connector shares the author's account. I'll merge once unit-and-preflight is green.

Verified:

• I recomputed SHA-256 for all 8 declared files (3 XSDs each for 2026v3.0/v4.0, plus both rules .xlsm) from the installed irs/ copies. All match the manifest.
• The manifest shape fits scripts/testing/irs.ts. rules packages are keyed by filename, so later code that references irs/rules/1040_Business_Rules_2026v{3,4}.0.xlsm will count as declared.
• Metadata only: no code, tax values, cases or baselines changed. No tax-accuracy sign-off is needed.

Non-blocking nits for a later PR:

• README says "ATS-valid from 2026-08-13" for v3.0. 08-13 is the IRS release date; please confirm it against the ATS publication schedule, or reword it to "released 2026-08-13".
• The existing README source paths end with the extracted dir (› 2026v1.0/); the new rows don't. The .pdf rules are listed in the README but not hashed in the manifest. Hash them, or drop "(+ .pdf)", if the PDFs aren't meant to be tracked.