v0.9.0

Theme: clever token budgeting. --budget maps are unchanged at L0 — this
release only changes what happens under pressure. Unbudgeted maps are
byte-identical to 0.8.0 (verified on three corpora, modulo the state
stamp).

Added

• Makefile support — Makefile/makefile/GNUmakefile/*.mk render
  as one node with each target as a command carrying its caller-settable
  variables: deploy(ENV,MANIFEST) means the recipe consumes $(ENV)
  (overridable ?= or undefined) and $(MANIFEST); variables the file
  pins with =/:= are internal and excluded. .PHONY and friends,
  pattern rules, and define bodies are skipped; _name targets are
  private. No parser dependency — a line scanner, like Helm.

Changed

• The degradation ladder is repaired and deepened to a skeleton floor.
  The old ladder was lumpy (one level dropped −1,921 tokens on the
  reference corpus while another dropped −116), partly broken (the private
  wipe left per-class - name lines at every level), and shallow (floor
  −17%; an 8k budget was unreachable). The new ladder (measured per-level
  on the reference corpus): L1 coverage edges (−5%), L2 helper signatures
  (−8%), L3 all private inventories (−8%, bug fixed), L4 chains of
  untested functions (−6%, replaces the no-op), L5 methods of types with
  zero real fan-in (−3%, replaces the name-keyed heuristic), L6 all chains
  (−4%), L7 the skeleton — no method lines, const values gone, type
  headers with fields and top-level signatures stay (−21%). Floor on the
  reference corpus: 7,138 tokens, −54% from the full map. Every level
  is monotone; facts degrade in usefulness order; the legend only explains
  what survived; nothing is ever cut mid-fact.
• Const values survive to the skeleton, and degraded maps disclose
  their losses. The first gate round dropped const values at L1 — the
  smallest saving (−0.3%) — and produced the worst failure: agents
  confidently answered value questions off a map that silently omitted
  the values. Now scalars ride to L7, and every degraded map carries a
  header disclosure naming the dropped fact classes with an instruction
  to read the source instead of guessing — measured to flip wrong
  zero-read route answers into correct one-read answers.
• The budget ladder no longer re-reads every source file per level
  (level-invariant work — LOC count, call resolution, helper detection —
  is computed once).

Dev

• Benchmark task files accept a top-level budget, applied to the
  map-bearing conditions' build.

Gates (measured before merge)

• Determinism, monotonicity, floor reachability: pass (numbers above).
• Refactor invariance: unbudgeted digests identical to v0.8.0 on the
  reference corpus, this repo, and the polyglot fixtures.
• Navigation at the skeleton floor: see benchmark/README.md.