docs(vrs): define Agent Spec field-change reconciliation

[myobie]

Summary

• rewrite the Agent Spec field-change VRS as a compact, field-first st2 conformance contract
• give F01 through F16 stable anchors and repeated lookup sections
• keep shared normalization, proof, ownership, ordering, and notification rules once
• state incomplete-proof behavior directly in terms of agents, tasks, files, processes, and ownership
• retain the compact execution order, implementation gaps, and acceptance cases
• remove the technical-term and action/report glossaries

Authority boundary

The canonical Agent Spec and proof corpus live in compoundingtech/evals at exact merged commit e9b53e79b05b1c0e1d7eea02db2eaba47376fe05, pinned there to st2 9887b2842222def0838c2cd82e6c24c218f7efa6.

st2 is one implementation; it does not own or copy the Agent Spec. Another implementation, including a future st3, can target the same contract and proof suite. This PR describes desired st2 conformance and st2-specific gaps. Cross-implementation field-change semantics remain proposed until the canonical evals specification and proof corpus adopt them.

Every field section links separately to:

1. the most specific pinned evals authoring section or exact lines;
2. the current st2 source definition;
3. st2 implementation or reconciler evidence.

The pin predates three fields used by this PR: Resource bindings, argv, and task lifecycle. The relevant sections state those gaps explicitly.

Preserved field decisions

• host changes are independent host-local remove/add projections, never migration
• workspace changes keep healthy work, commit live context, write one durable event, then try transport-neutral DING
• catalog and PTY roots are not Agent Spec fields
• spawn-input and command drift stay visible without automatic restart
• identity and task-address changes use exact remove-old/add-new
• render and Resource changes notify surviving agents only after commit
• compact DING, future policy, retirement, invalid-state, and provider-boundary rules retain their corrected F01-F16 behavior
• moved intent remains unsupported and subordinate to implemented field behavior

Size and semantic diff

Against review-red exact head bc8483a6de557679a893a54c1332c2b0ef2bf7ba:

• requirements.md: 97 lines / 789 words → 98 lines / 808 words
• spec.md: 285 lines / 1,637 words → 292 lines / 1,711 words
• total: 382 lines / 2,426 words → 390 lines / 2,519 words
• patch: 61 additions, 53 deletions
• semantic delta: replace undefined component/scope jargon with explicit agent/task/file proof and refusal rules; clarify convert language, exact resolved paths and Resource references, st2 ownership retention, and F02/F09/F10 removal boundaries; advance the canonical evals authority and exact-line links; preserve all SPEC-R01-R06, F01-F16, G01-G08, ordering, notification, and acceptance semantics

Against prior exact head 2128945cccc043a09f6e44f4963e856f802d4532:

• requirements.md: 205 lines → 98 lines
• spec.md: 321 lines → 292 lines
• total: 526 lines / 4,088 words → 390 lines / 2,519 words
• patch: 372 additions, 508 deletions

The branch is restacked on current main exact a8c57122b878c48e2f4cad79925534cdbb863ac0. The rebase itself changed no PR document bytes. The PR remains docs only; it changes no runtime, command, catalog, provider, or test behavior.

Validation

At exact head 069553a848f7e2f587ba8e748ccefc4659823983:

• all 16 field anchors are unique and linked directly from requirements
• all local link targets resolve
• all pinned evals anchors resolve at e9b53e79; exact supported-field lines 79-101 and explicit-task lines 153-157 were checked
• the nested st2 proof pin remains exact 9887b2842222def0838c2cd82e6c24c218f7efa6
• issues Expose desired versus observed launch generation for adopted tasks #40, Add a true no-write dry run for st2 up --once #53, and Define a guided migration operation for state-bearing st2 paths #85 resolve
• no component/scope shorthand from the review-red remains
• zero PR conversation comments, reviews, or review threads
• semantic audit covers SPEC-R01-R06, F01-F16, and G01-G08
• cargo test --test invariants -- --test-threads=1
• cargo test --doc --workspace
• git diff --check
• hosted Nix: run 30631108580, job 91157400155 passed for this exact head

Review state

This PR remains draft, reviewer-free, unmerged, and implementation-free. CoS will review the exact head before any ready or merge action.

[myobie]

CoS exact review is green at 069553a. The compact field-first contract keeps the reviewed semantics and corrects the four final clarity defects: plain convert wording, exact F01 comparison inputs, grammatical ownership retention, and the F13 identity/child removal references. Hosted Nix is green. GitHub cannot record an approval because the active GitHub identity opened this PR. Nathan authorized CoS review and merge of this documentation.