Add sample links exercising every resolver branch

Extend the sample org data with links that cover each resolve_target
dispatch path, so the link-navigation feature can be exercised by hand
and in the GUI.

test.org:
- Add a <<intro-anchor>> dedicated target and a #+NAME: languages-table
  named element as link destinations.
- Add "Same-file links" and "Cross-file links" subsections listing one
  link per kind: external URL, #custom-id, *headline, dedicated target,
  named element, plain text, and file:notes.org[::target] forms.

notes.org (new):
- Second document providing cross-file targets: *Meeting Notes headline,
  #design-decision custom id, <<release-anchor>> dedicated target, and a
  #+NAME: roadmap-table named element.
- Includes a back-link to test.org and its own same-file links.

All 14 links verified to resolve over a live server (dedicated/fuzzy
kinds, same-file, cross-file, and back-link directions). Property
drawers are placed directly under their headlines so CUSTOM_ID targets
parse; the plain-text target phrase is chosen so sorted-order section
scanning lands on the intended prose.

notes.org

@@ -0,0 +1,42 @@
+#+TITLE: Orkmode Notes
+#+AUTHOR: Test User
+#+FILETAGS: :notes:sample:
+
+* Meeting Notes
+:PROPERTIES:
+:CUSTOM_ID: meeting-notes
+:END:
+
+Notes captured during planning meetings.
+
+Back-link to the test document: [[file:test.org::*Introduction][Introduction in test.org]].
+
+** Design
+:PROPERTIES:
+:CUSTOM_ID: design-decision
+:END:
+
+We decided to keep all org logic in the server and treat clients as thin 9P
+consumers. See the showcase in [[file:test.org::#high-priority][the high priority task]].
+
+* Release
+
+<<release-anchor>>
+Checklist for cutting a release:
+
+- [ ] Bump version
+- [ ] Run full test suite
+- [ ] Tag and push
+
+A same-file link to the [[*Meeting Notes][meeting notes]] above.
+
+** Roadmap
+
+#+NAME: roadmap-table
+| Version | Theme            | Status      |
+|---------+------------------+-------------|
+| v0.3    | Read-only GUI    | done        |
+| v0.4    | In-place editing | in progress |
+| v0.5    | Agenda views     | planned     |
+
+Reference the table with [[roadmap-table][the roadmap table]].

test.org

@@ -11,6 +11,9 @@ This is a test document for the orkmode parser.
 
 It contains various org-mode constructs to verify parsing.
 
+<<intro-anchor>>
+This paragraph is marked with a dedicated target used by same-file links.
+
 * TODO [#A] High Priority Task :urgent:work:
 DEADLINE: <2025-01-15 Wed 14:00 +1w>
 :PROPERTIES:
@@ -72,6 +75,7 @@ date
 
 ** Tables
 
+#+NAME: languages-table
 | Name    | Language | Stars |
 |---------+----------+-------|
 | Emacs   | Lisp     | 10000 |
@@ -99,6 +103,27 @@ Some text with a [[https://orgmode.org][link to org-mode website]].
 
 Internal link to [[#high-priority][the high priority task]].
 
+*** Same-file links
+
+Links that resolve within this document:
+
+- External URL: [[https://orgmode.org][org-mode website]]
+- Custom ID: [[#high-priority][High Priority Task]]
+- Headline title: [[*Reference Material][jump to Reference Material]]
+- Dedicated target: [[intro-anchor][go to the Introduction anchor]]
+- Named element: [[languages-table][see the languages table]]
+- Plain text: [[has been completed][jump to the completed-task prose]]
+
+*** Cross-file links
+
+Links that resolve into =notes.org=:
+
+- Whole file: [[file:notes.org][open the notes document]]
+- Headline in file: [[file:notes.org::*Meeting Notes][Meeting Notes in notes.org]]
+- Custom ID in file: [[file:notes.org::#design-decision][a design decision]]
+- Dedicated target in file: [[file:notes.org::release-anchor][the release checklist anchor]]
+- Named element in file: [[file:notes.org::roadmap-table][the roadmap table]]
+
 ** Math and LaTeX
 
 Inline math: $E = mc^2$