ed: add the conforming line editor dependency

[brandonpayton]

Purpose

Publish GNU ed as a first-class Kandelo package so patch application and other POSIX build workflows have a conforming line editor instead of the deliberately small posix-utils-lite applet.

Changes

• build GNU ed 1.22.5 from the verified upstream source archive with the Kandelo SDK;
• keep lzip as a host-only extraction dependency and avoid introducing a target sed dependency;
• pass the cross compiler through ed's custom configure interface;
• instrument the editor with Kandelo's fork continuation tool because ed shell escapes call fork;
• install ed, a relocatable POSIX-shell red wrapper, manpages, and Info documentation;
• declare the source's actual GPL-2.0-or-later license;
• test GNU Patch's exact ed - FILE invocation shape, editing commands, shell execution, and restricted mode.

The red wrapper replaces upstream's sed-based path rewrite with equivalent POSIX parameter expansion. This avoids an undeclared target sed runtime dependency and leaves /bin/sh as the normal Kandelo base-system boundary.

Evidence

The formula semantics are unchanged from the previously reviewed ABI-18 build:

• a clean source build completed from semantic head b74e858;
• literal brew test automattic/kandelo-homebrew/ed passed under Node;
• the test covered version reporting, substitution, append/write, a forked shell escape, GNU Patch's ed - FILE form, and restricted shell rejection;
• the exact installed ed and red passed the same process-path workflow in Chromium;
• artifact inspection reported ABI 18, only env/kernel imports, all five wpk_fork_* exports, no legacy Asyncify, and no Cellar or host paths.

The three-commit branch is now based on tap main e05afec, which includes Dash, zstd, PCRE2, and Make. Every artifact-producing formula line after the support import is byte-identical to the validated 6c6c82f head; the final commit changes only loading to the installed Tap.fetch path. Current head is 6d75f4342c3791318795c333db09013c663b2a05.

Current rebase validation through Kandelo's dev shell passed Homebrew Ruby syntax, brew style, literal installed-tap loading, git diff --check, and the shared Formula support suite (21 runs, 186 assertions). The formula tail matches the validated head exactly; no source build or runtime suite was rerun for this history-only rebase.

Upstream make check was not run because its host shell executes the cross-compiled editor directly. The Node and Chromium formula workflows instead exercised the target program through Kandelo.

The prior disposable bottle SHA-256 9a5043665b32f4fe38ca9301bd3799329b853199ca1cdacbbbe15b2f26cc87f6 is historical validation only. It is rejected for publication after the rebase and platform changes and must not be copied into a bottle block.

Source merge and bottle gates

Automattic/kandelo#867 is merged and is no longer a gate. The source formula may merge independently after a fresh formula review; it contains no bottle block or sidecar. Bottle construction, publication, and any installability claim remain gated until:

• sdk: reserve an 8 MiB main-thread shadow stack for linked programs kandelo#842 has landed for the linked-program shadow-stack floor;
• Build fork instrumentation from the repository workspace kandelo#873 has landed so clean external-directory builds can create the fork instrumentation tool;
• Reject stale Wasm artifacts with aliased ABI exports kandelo#882 has landed so materialization rejects aliased stale-ABI exports;
• Test fork instrumentation output reproducibility across processes kandelo#888 has landed so fork-instrumented bottle bytes are reproducible;
• ci: isolate and verify Homebrew bottle publication kandelo#881 has landed so privileged publication does not consume unreviewed Actions caches;
• homebrew: preserve bottle compatibility for host build dependencies kandelo#887 has landed so the host-only lzip dependency can use compatible Homebrew bottles;
• homebrew: publish tap-native formulas without registry duplicates kandelo#885 has landed so tap-native sidecars do not require a registry duplicate;
• tap ci: add thin tap workflows for bottle publishing and maintenance #22 is used only if a branch-based pre-merge bottle dry run is needed;
• trusted ABI-18 bottles are built from the final PR head after those prerequisites and pass sidecar generation, stock guest pour, Node, and Chromium tests;
• the final tap CI/check set is green.

This PR publishes wasm32 only. Firefox, WebKit, and wasm64 were not validated and are not claimed. No Kandelo main-repository files or ABI definitions change here.

[brandonpayton]

Devil’s-advocate source-only review at 6d75f4342c3791318795c333db09013c663b2a05: ACCEPT. The diff contains only the formula and README; no bottle block or sidecar. Upstream archive/license, build-only lzip edges, relocatable red wrapper semantics, fork instrumentation, exact install outputs, and source tests were audited. Fresh dev-shell checks passed Ruby syntax, brew style, installed-tap loading, the shared support suite (21 runs / 186 assertions), ancestry, and diff checks. Bottle publication and installability claims remain explicitly gated and are not part of this merge.