feat: support manual ordering of groups and feeds

[mlkgrnt]

PR: feat: support manual ordering of groups and feeds

分支 feat/group-feed-reorder · 单 commit c53b5923 · 基于 upstream main (d2b979cc)
15 files changed, 887 insertions(+), 34 deletions(-)

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Problem

Groups and feeds always render in a fixed order (the order they were created in the database), with no way for the user to arrange them. Once a user subscribes to many feeds, the list becomes hard to scan and important groups/feeds cannot be surfaced to the top. There is also no way to create an empty group to organize feeds into before subscribing to anything.

Changes

UI: drag-and-drop reordering (FeedsReorderMode.kt, new)

• The feeds page title row gains a sort button (Icons.Rounded.SwapVert). Tapping it switches the content into FeedsReorderMode.
• In reorder mode:
  • Whole groups can be dragged up/down via rememberReorderableLazyListState (lazy list variant).
  • Feeds inside each group can be dragged via the embedded non-lazy ReorderableColumn with a handle on each feed row.
  • A top toolbar shows a hint (reorder_tips) and a Done button to exit reorder mode and persist the new order.
• Uses sh.calvin.reorderable:reorderable:3.1.0 (KMP library; the Android artifact resolves through its reorderable-android variant).

UI: create empty group

• The title row also gains a ＋ button (Icons.Rounded.Add) that opens a name dialog (TextFieldDialog), letting the user create an empty group before adding any feeds. (Previously groups could only be created implicitly when subscribing a feed.)

Data layer

• Feed and Group entities gain a position: Int column with @ColumnInfo(defaultValue = "0") so the SQL-level default satisfies the AutoMigration from schema 7 → 8 (a NOT NULL column without a default would fail migration).
• Feed's secondary constructor was extended with position to keep Room's constructor matching working (the primary constructor carries @Ignore important and therefore never matches the column set directly).
• AndroidDatabase version bumped 7 → 8 with the exported 8.json schema.

ViewModel

• FeedsViewModel gains addGroup(name), reorderGroups(ids), and reorderFeeds(groupId, ids) which update the position columns transactionally.

Verification

• :app:compileGithubReleaseKotlin — BUILD SUCCESSFUL
• :app:testGithubReleaseUnitTest (same command the upstream CI runs) — BUILD SUCCESSFUL, all tests green