feat(picker2): complete Picker2 prototype

Picker2 replaces the original Picker1 with a two-phase (tag → pick) +
mask-bitmap architecture, decoupling argument matching from type
conversion via a composable matcher pipeline.

Architecture
- FlagMatcher — boolean flags (--verbose)
- ArgMatcher — single flag+value pairs (--name Alice)
- MultiArgMatcher — multi-value flag groups (--files a.txt b.txt)
- PositionalMatcher — positional arguments, respects `--`
- SingleMatcher — composite for Single-type Pickables

Types
- Flag (Active/Inactive) — semantic bool flag value
- String + 14 numeric types via SinglePickable trait
- Vec<T> — greedy multi-value (all SinglePickable types)
- VecUntil<T> — bounded multi-value via BoundaryCheck trait
- VecUntil<T>, pick_string, pick_numbers, pick_bool, pick_flag

Style system
- UNIX_STYLE (kebab), POWERSHELL_STYLE (Pascal), WINDOWS_STYLE (Pascal)
- naming_case auto-conversion via just_fmt integration
- Style-aware separator (= for Unix, : for PS/Windows)

Infrastructure
- internal_repeat! macro generates PickerPattern1..=32
- SinglePickable blanket impl → Pickable
- MultiPickableWithBoundary trait with greedy/bounded variants
- 151 integration tests
- Docs updated for parser feature

1 files changed, 7 insertions, 1 deletions

diff --git a/.vscode/settings.json b/.vscode/settings.json
index 0aa6db4..7472e1c 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,5 +1,11 @@
 {
   "rust-analyzer.check.command": "clippy",
   "rust-analyzer.checkOnSave": true,
-  "rust-analyzer.linkedProjects": [".run/Cargo.toml"],
+  "rust-analyzer.linkedProjects": [
+    ".run/Cargo.toml",
+    "mingling_picker/Cargo.toml",
+    "mingling_pathf/test/Cargo.toml",
+    "mingling_picker/test/Cargo.toml",
+  ],
+  "rust-analyzer.cargo.features": ["mingling_support"],
 }