feat(layout): support do (obtain diff hunk) keymap in diff1_inline layout

[dlyongemallo]

No description provided.

[Copilot]

Pull request overview

Adds support for obtaining (“diffget”) the old-side hunk in the diff1_inline (unified inline extmark) layout, where native Vim diff mode is disabled.

Changes:

• Implement Diff1Inline:diffget(first, last) to splice old-side content into the live buffer based on cached vim.diff hunks.
• Route actions.diffget() to the inline-layout implementation when the current layout is Diff1Inline, including visual-range support.
• Add inline_diff.get_hunks(bufnr) accessor, wire up the do keymap for diff1_inline, and add functional tests for Diff1Inline:diffget.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
lua/diffview/scene/layouts/diff_1_inline.lua	Adds the inline-layout diffget splice implementation operating on cached hunks/old lines.
lua/diffview/actions.lua	Extends actions.diffget to special-case Diff1Inline and apply hunks over a cursor/visual range.
lua/diffview/scene/inline_diff.lua	Exposes cached hunk list via get_hunks(bufnr) for consumers like Diff1Inline:diffget.
lua/diffview/config.lua	Adds do mapping for diff1_inline and updates comment about native diff limitations.
lua/diffview/tests/functional/layouts_spec.lua	Adds functional coverage for Diff1Inline:diffget across add/change/delete and range cases.

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.

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