Adopt engine v7: paren-based wrapped-state naming in `Path` format + docs

[mellonis]

Tracking the consumer-side adoption of engine v7's paren-based wrapped-state naming in @post-machine-js/machine. Gated on turing-machine-js#168 merging and shipping in engine v7.

Why

PostMachine's Path format embeds > as the engine's wrapper separator — see paths like 'foo>10~30' in the README's naming-convention section. Engine v7 changes the wrapper format from flat bare>override to nested bare(override). Once engine v7 publishes, PostMachine paths need to adopt the new format to stay consistent with what state.name / MachineState.arrivalPath carry.

Scope

Code (parser + formatter):

• Path parser/formatter — whichever module owns parsePath(s) / formatPath(p). Adopt (...) for wrapper composition. The ~ continuation separator and :: subroutine scope separator are unaffected.
• Anywhere PostMachine builds paths internally using the wrapper convention — audit MachineState extension code.

Docs:

• packages/machine/README.md — naming-convention section's > separator description, all example paths.
• CLAUDE.md — engine-naming-convention references.

Tests:

• Any path-format assertion using > for wrappers (e.g., 'rightToBlank>1~2' shape) — flip to 'rightToBlank(1~2)'.
• states.md / Mermaid samples in test fixtures.

Out of scope (frozen historical record)

• packages/machine/CHANGELOG.md — v6.x entries documented the old format; leave as-is.
• docs/superpowers/specs/, docs/superpowers/plans/ — frozen planning artifacts; existing notes about wrapper naming stay correct in their historical context.

Coordination

• Lockstep with #72 (lockdown for intermediate engine-graph states) and #82 (rename adoption) — all three land in the post-machine-js v7 release.
• v7 work in this repo lands on the v7 integration branch.
• Bundling thought: Adopt engine v7: rename withOverrodeHaltState → withOverriddenHaltState consumer-side #82 + this issue can ship in a single PR (both are mechanical format adoptions across the same file set). Extend defineProperty lockdown to intermediate engine-graph states (continuations, hoppers, group wrappers) #72 is structural and warrants its own PR.

Migration for consumers (when v7 ships)

Any code that pattern-matches state.name or MachineState.arrivalPath for wrapper composites needs to switch from >-split to paren-aware parsing. Most users don't introspect paths beyond top-level scope/index — impact is concentrated in tooling and tests, not application code.

[mellonis]

Engine PR status: turing-machine-js#169 is open against the engine v7 branch. Closes engine #138/#139. The paren-naming change (turing-machine-js#168) that this issue tracks adoption of is already merged.

Scope unchanged: PostMachine's Path parser still embeds > as the wrapper separator ('foo>10~30' shape). The engine's bare>override → bare(override) flip means this Path format needs the corresponding adoption. PR #169's broader emit changes (subgraph, halt-marker, brackets, idle sentinel, thick arrows) don't affect this issue — those touch engine toMermaid output, not post-machine-js's Path format.

Bundling suggestion: #82 (rename adoption) can ride in the same PR as this one — both are mechanical adoptions, overlapping files.

Engine vocabulary note (out of this issue's strict scope): once engine v7 publishes, any post-machine-js docs that show engine-rendered state graphs of PostMachine instances will paint in the new format — bracketed edge labels (['X'] → [K]/[R]), K/E/B/🞰 glyph vocabulary, halt-frame subgraphs around wrapped states. If post-machine-js docs include any such diagrams (Mermaid blocks in READMEs, design docs), they'll need a regen pass alongside this Path-format adoption.

[mellonis]

v7-alpha.1 published. Engine PR #169, #170 merged; alpha.1 includes the paren-based wrapped-state naming (#148 upstream) that this issue tracks adoption of, plus the broader emit overhaul (#138/#139 upstream). Install:

npm install @turing-machine-js/machine@7.0.0-alpha.1

This issue's strict scope (flip > to parens in PostMachine's Path format + parser) is now adoptable. Engine v7's broader emit changes (subgraph, halt-marker, bracketed labels, etc.) are out of this issue's scope but worth a separate sweep for any post-machine-js docs that embed engine-rendered Mermaid blocks — those need a regen pass alongside this adoption work.

Suggested bundling with #82 stands.

Release notes: https://github.com/mellonis/turing-machine-js/releases/tag/v7.0.0-alpha.1

[mellonis]

Shipped in v7.0.0-alpha.2 via #84. Closing for v7 milestone bookkeeping — work has been on the v7 integration branch since 2026-05-21. (Release PR #92 still references this issue for historical trace.)