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

Cut the first vertical slice through both layers: a runnable
`kitchen view <file>` that reads a Recipe File, parses it, and renders
it styled to the terminal.

@kitchen-md/core exposes a pure, total `parse(input): DocumentAST` built
on a minimal remark pipeline (parse + frontmatter) with a translation
layer to core's own AST types — frontmatter passthrough, HeadingBlock,
ParagraphBlock, and TextNode. remark types never leak into the public
API.

@kitchen-md/bin's `view` subcommand (commander) reads the file and hands
the DocumentAST to a pure `render(ast): string` (chalk, ANSI
auto-suppressed off a TTY). Fallible file I/O is modelled as a neverthrow
Result over a tagged-union CliError, matched at the boundary: stdout on
success, stderr and exit 1 on failure. The command functions sit beside
the import.meta.main-guarded CLI entry so they are testable in-process.

Tests follow ADR 0009's tiers — unit (parse, render), integration (the
view command's Result), and e2e (the binary as a subprocess) — with
coverage, a path-scoped test-report generator, and a prose fixture
rounding out the tooling. ADR 0008 records errors-as-values at the CLI
boundary; ADR 0009 records the testing tiers.

.gitignore

@@ -7,6 +7,12 @@ packages/bin/kitchen
 result
 result-*
 
+# test coverage output
+coverage/
+
+# generated test report and its intermediate artifacts
+reports/
+
 # direnv / nix-direnv cache
 .direnv/