BE-042: formal context model — context(cwd) as a total function, one law for CLI and pager

Now: OPEN

The context URI must be DERIVED, never improvised: a process start or a navigation yields address(tree) + subpath, and every verb then resolves relative args via resolve(context, base, rel) BE-030. Today each consumer guesses its own anchor: the CLI drops the cwd sub-path BE-032, //X anchoring mis-fires across sub mounts BE-034 BE-039, and the cwd-rebase resolver sits unmerged URI-010. This ticket pins the formal model; Nav gets rewritten from it once the open rulings land.

Input

Context

Ruling seed (gritzko, 2026-07-10): in ~/src/journal/wiki the implied context is //wiki — journal is a PROJECT root (Project: the top-level repo holding meta/wiki/todo/html/work), not a worktree and not a submodule; the project's own name never enters the context URI.
Live repro same day: cd wiki && jab delete Sniff.mkd → "0 row(s), 1 skipped" while jab delete wiki/Graf.mkd from the root deletes; full bare-arg verb matrix (cat/log/why silently EMPTY from a subdir) recorded in BE-032.
Prior art this model must subsume: BE-030 resolve(context,base,rel) landed; BE-031 hive (worktrees at <meta>/work/NAME); BE-033 scheme-less //X is never a cached remote; BE-037 // = the launch top everywhere; URI-010 cwd-rebasing rules (implemented in wt //URI-010, unmerged).

Goals

context(cwd) is TOTAL: climb cwd to the nearest .be anchor giving tree T and sub-path P (cwd = root(T)/P); context = address(T) joined with P.
address(T): the PROJECT root → bare // (the unnamed top, per BE-037); a hive worktree work/N → //N BE-031 (the work/ layer elides, Project §5); a submodule mounted at M → address(parent tree) joined with M.
Joining with the bare // root puts the FIRST sub-path segment in the authority slot: ~/src/journal/wiki → //wiki; ~/src/journal/be/core → //be/core; ~/src/journal/work/BE-038/src → //BE-038/src.
Verbs resolve every arg as resolve(context, arg): relative args join the context (then NAVESCAPE-confined); absolute paths and scheme/authority URIs bypass, exactly the URI-010 trigger rule.
CLI and pager derive the context through ONE composer, byte-identical results; Nav and Worktree rewritten from the ruled model (both stale per BE-030).

Constraints

The pure URI grammar stays cwd-agnostic; composition lives in be/ (discover.js navCwd/find) URI-010.
Correct wt-root-relative semantics (e.g. be put . at the root, whole-tree get) must not shift BE-032.

WIP

Design decisions

OPEN RULING (gritzko): //X lookup order when X could be BOTH a hive worktree work/X and a first-level tree entry X (dir or sub) — work/-first, entry-first, or NAVNONE on collision? BE-031 said "//NAME = work/NAME, fixed convention"; the //wiki ruling adds first-level entries as authorities.
OPEN RULING (gritzko): is a plain-dir authority like //wiki addressable from OUTSIDE its tree (from another worktree's context), or only ever produced as an implied cwd context?

TODOs

Settle the two rulings above; then rewrite Nav (+ prune todo_root machinery per BRO-023) and the Worktree context section from the model.
Repro tests: context derivation for each node kind — root subdir (wiki/), hive wt (work/N/…), sub mount (be/…), nested sub.
Rebase + merge wt //URI-010 (resolveWtPath) under this model, then the BE-032 wtpath call-site sweep on top.

Blockers and bummers

URI-010 merge risk: main landed URI-015 082b172c touching the same put/post intake paths — rebase before merge.