docs: de-hype slice 1 — technicalize body prose (README + RFC-1 program docs)

[maxine-at-forecast]

First slice of the de-hype pass (#287, umbrella issue on GitHub: #6).

Standard applied

Default to precise technical claims; keep narrative flair only in localized intro/conclusion sections. The README's opening thermite metaphor stays (it's the project's identity); body and mechanism prose gets technicalized. No change to any claim, requirement, acceptance criterion, identifier, or structure — tone only.

Changes (5 files)

• README.md — "exactly the bottleneck" → "the bottleneck"; "The sharpest possible objection" → "The hardest objection"; "precisely what makes … feasible" → "what makes … feasible". (Metaphor and overall pitch intact.)
• .design/thermite2-program.md — dropped "— a delta in the program's favor" and "which is exactly why".
• .design/m0-spikes.md — dropped "the plan analysis's most material correction" and "the asymmetry is safe" framing; kept the engineering rationale (why n=4 is insufficient, the downward bias).
• .design/stage1-forge-tier.md — "The headline that lands at gate G1" → "The behavioral change at G1".
• .design/stage3-bv-reconstruction.md — dropped "for exactly that reason" / "whole ladder".

(stage2-stratified-cage.md was already technical — no change.)

Scope / next slices

Sampling found the docs more disciplined than a broad "hype" sweep implies — RATIONALE.md actively hedges its claims. So this is a measured dial-down, not a rewrite. Remaining slices:

• Slice 2: body prose in the public docs (RATIONALE.md, thermite-design.md) and the other .design/ areas — more judgment-heavy, public-facing.
• Slice 3: source comments (*.rs/*.lean) — emphatic ALL-CAPS and editorializing.

🤖 Generated with Claude Code

[maxine-at-forecast]

Superseded by the deeper whole-repo tone pass: slice 1 only trimmed adverbs, but the real fix is the defensive→affirmative register change (.design/tone-and-voice.md). Redoing these docs at that depth.