feat: add kitchen view command and parser skeleton (task 0003)

Cut the first complete thread through both layers with the smallest set
of node types.

@kitchen-md/core gains a pure, total `parse` returning a
`DocumentAST` of `{ frontmatter, blocks, diagnostics }`, built from a
minimal remark pipeline (remark-parse + remark-frontmatter) with an
internal translation layer to core's own types. This slice models
frontmatter passthrough, HeadingBlock, ParagraphBlock, and TextNode;
remark's mdast does not surface in the public API.

@kitchen-md/bin gains the `view` subcommand (commander) that reads a
file, calls `parse`, and passes the AST to a pure `render` that returns
an ANSI-styled string via chalk (auto-suppressed off a TTY). Frontmatter
prints as raw YAML followed by a separator, headings styled distinctly
by level, paragraphs as prose. A missing argument prints usage and a
missing/unreadable file a human-readable error, both exiting 1.

Richer blocks/inline plus raw fallbacks are task 0004; malformed
frontmatter diagnostics and the basic.md smoke test are task 0007.

.claude/tasks/0003-view-skeleton.md

@@ -0,0 +1,71 @@
+---
+spec: cli-view
+---
+
+## What to build
+
+The walking skeleton: a runnable `kitchen view <file>` that reads a Recipe File, parses it, and prints it styled in the terminal.
+This slice cuts the first complete thread through both layers with the smallest set of node types.
+
+In `@kitchen-md/core`, stand up the `parse` function and the types module, modelling only what this slice renders: frontmatter passthrough, `HeadingBlock`, `ParagraphBlock`, and `TextNode`.
+Set up the minimal internal remark pipeline needed for these (parse + frontmatter), with the translation layer from remark's output to core's own types.
+`parse` is a pure, total function returning a `DocumentAST` of shape `{ frontmatter, blocks, diagnostics }`.
+
+In `@kitchen-md/bin`, implement the `view` subcommand with commander taking one required file-path argument.
+The entry point owns file I/O: it reads the file, calls `parse`, and passes the `DocumentAST` to a pure `render(ast)` function.
+`render` walks the AST and returns an ANSI-styled string using chalk, which auto-suppresses colour when stdout is not a TTY.
+Frontmatter prints as raw YAML followed by a visual separator, then the body: headings styled by level, paragraphs as prose with blank-line spacing.
+
+The demoable outcome: `kitchen view <recipe.md>` shows metadata, headings, and prose; a missing file prints a human-readable error to stderr and exits non-zero.
+
+## Acceptance criteria
+
+- [x] `parse` returns a `DocumentAST` `{ frontmatter, blocks, diagnostics }`; frontmatter is a plain object (empty when absent), diagnostics empty in the normal case
+- [x] Core types live in a dedicated types module and are re-exported from the package entry point alongside `parse`
+- [x] Headings (levels 1–6) and paragraphs are modelled as `HeadingBlock` and `ParagraphBlock`, with paragraph content as an inline array of `TextNode`
+- [x] Blocks are flat and in document order (a heading is a sibling of the following paragraph, not its parent)
+- [x] remark types do not appear in core's public API
+- [x] `kitchen view <file>` reads the file, calls `parse`, and prints the rendered output
+- [x] `render(ast)` is pure (no I/O, no side effects) and returns an ANSI-styled string
+- [x] Frontmatter renders as raw YAML before the body, followed by a visual separator
+- [x] Headings render bold and distinct by level; paragraphs render prose followed by a blank line
+- [x] chalk styling is suppressed automatically when stdout is not a TTY
+- [x] A missing file path prints commander usage to stderr and exits 1; an unreadable/nonexistent file prints a human-readable error to stderr and exits 1
+- [x] Renderer unit tests (ANSI stripped) cover frontmatter, the separator, headings, and paragraphs
+- [x] Core unit tests cover frontmatter passthrough (arbitrary fields, empty, absent), headings at every level, and paragraphs with `TextNode` content
+
+## Implementation Notes
+
+All acceptance criteria are met. The following decisions and scope boundaries are worth recording.
+
+### Scope boundaries carried by the slice
+
+Only `HeadingBlock`, `ParagraphBlock`, and `TextNode` are modelled, as the slice specifies.
+The remark→core translation therefore skips any block that is not a heading or paragraph (lists, blockquotes, code, thematic breaks), and `translateInline` keeps only text nodes, dropping every other inline node type.
+The drop is by whole node, so emphasised or linked text is currently lost, not merely unstyled.
+This is within task 0003's stated scope; the lossless `RawInline`/`RawBlock` fallback and the typed `EmphasisNode`/`StrongNode`/`LinkNode` land in task 0004, which also makes the translation recurse into container children.
+
+Malformed-frontmatter handling is out of scope here and owned by task 0007.
+This slice parses well-formed frontmatter and returns `{}` for the empty and absent cases; a genuinely malformed YAML block would currently throw from the YAML parser.
+The total-function guarantee for that case (returning `{}` plus an `invalid-frontmatter` diagnostic) arrives with 0007.
+
+### Types defined ahead of full use
+
+`Diagnostic`, `Point`, and `Position` are defined in the types module because `DocumentAST.diagnostics` is typed `Diagnostic[]`, even though only the empty case (`diagnostics: []`) is produced in this slice.
+This keeps the public shape stable; 0007 populates the channel.
+
+### Rendering decisions
+
+Headings render distinct-by-level via chalk, tapering from bold at level 1 toward dim at level 6; a heading is followed by a single newline and a paragraph by a blank line, which is what visually separates them once ANSI is stripped.
+Per the cli-view spec, the specific colour and weight choices are visual decisions verified by inspection, not asserted in tests — the renderer tests assert ANSI-stripped text, spacing, and the presence/absence of styling, not particular colours.
+The frontmatter separator is a dimmed 40-character box-drawing rule.
+
+### Tests that are green on arrival
+
+A few required-coverage tests document behaviour that the minimal implementation already satisfies and so pass without a preceding red (frontmatter empty/absent, flat document order, and the level-distinctness/suppression renderer test).
+They assert real observable behaviour against independent literals rather than restating the implementation.
+
+### Review follow-up applied
+
+The `runCli` and `stripAnsi` test helpers were extracted into `packages/bin/src/test-support.ts` to remove duplication the review flagged across the bin test files.
+The scaffold's remaining `test.todo` placeholders (future block/inline types, annotations, the smoke test) are left intact for their owning tasks.