mnote/.codex/reasonix-tasks/2026-05-25-batch-g-worker-d-5-29-block-dnd-helpers.md

Batch G Worker D: 5-29 block menu DnD helper boundary

Project root: /mnt/Data1T/mnote-worktrees/0525-g-worker-d-5-29-block-dnd-helpers

Goal

Move a narrow, testable helper boundary for block handle drag/drop hit testing out of rust/spikes/leptos-tiptap-spike/src/lib.rs.

This is a candidate patch only. Codex will review and selectively merge.

Allowed files

• rust/spikes/leptos-tiptap-spike/src/lib.rs
• rust/spikes/leptos-tiptap-spike/src/editor_runtime/mod.rs
• rust/spikes/leptos-tiptap-spike/src/editor_runtime/block_hover_state.rs
• You may add one new file under rust/spikes/leptos-tiptap-spike/src/editor_runtime/, preferably block_dnd.rs or a more precise local name.

Do not edit generated island files. Do not edit mnote-web files.

Expected shape

• Prefer extracting pure geometry/classification helpers used by pointer_in_handle_corridor, drop_indicator_from_target, or drop_indicator_from_point.
• Do not move Leptos signals, DOM listener closures, editor command dispatch, or HTML reorder behavior.
• Preserve current block menu delete/undo and drag/reorder behavior.
• Keep DropPlacement, DropIndicatorState, and HoveredBlockState ownership consistent with block_hover_state.rs.
• If a helper needs DOM rect values, pass primitives/structs in from lib.rs; do not invent a second editor-stage lookup layer.

Verification

Run these from the project root:

cargo fmt --manifest-path rust/Cargo.toml --all --check
cargo check --manifest-path rust/spikes/leptos-tiptap-spike/Cargo.toml
cargo build --manifest-path rust/spikes/leptos-tiptap-spike/Cargo.toml --target wasm32-unknown-unknown --release
wasm-bindgen rust/spikes/leptos-tiptap-spike/target/wasm32-unknown-unknown/release/mnote_leptos_tiptap_spike.wasm --target web --out-dir rust/spikes/leptos-tiptap-spike/generated/island --out-name mnote-leptos-tiptap-spike-island
NODE_PATH=/mnt/Data1T/mnote/node_modules node scripts/task489-block-menu-delete-undo-smoke.js
NODE_PATH=/mnt/Data1T/mnote/node_modules node scripts/task488-local-attachment-link-delete-undo-smoke.js

If wasm-bindgen changes generated files, report that fact but keep generated files out of the candidate diff unless required by the task.

Required output

• Produce process-handoff.md, process-handoff.json, result.json, and final.md.
• Include modified files, exact verification commands, pass/fail evidence, risks, and remaining work.
• Do not commit.
• Do not modify /mnt/Data1T/mnote.