refactor: split into idx-core library and idx-cli binary workspace

Phase 2 of docs/DESIGN.md, no behavior change:

- crates/idx-core (library): api, analysis, cache, config file handling
  and provider selection, curl_impersonate, error, ownership, runtime,
  plus the shared test fixtures. clap derives are behind an optional
  `clap` feature so the library does not require clap.
- crates/idx-cli (binary `idx`): cli/, output/, and IdxConfig (output
  format and color resolution). Package and binary names are unchanged.
- config.rs is split: file read/write and validation move to core; a
  CLI test keeps core's OUTPUT_VALUES in sync with OutputSetting.
- ownership::db::open_db/db_path drop their unused IdxConfig argument.
- One workspace version; shared dependency versions; no third-party
  version changes in Cargo.lock. LICENSE is symlinked into each crate.
- flake: workspace version, new source paths, and a per-crate package
  check (idx-cli is built from its tarball against packaged idx-core,
  since idx-core is not on crates.io yet). CI cache key, release path
  filter, and the golden whitespace-hook exclusion follow the new layout.

Parity: all 143 golden outputs match byte for byte without
regeneration; 157 core + 17 CLI unit tests (173 before plus the new
OUTPUT_VALUES sync test), 62 CLI tests pass. Live A/B against main:
16/16 stocks cases identical; ownership discover got IDX 403 on both
(exit 4 vs 1 is the phase 1 exit-code change).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/api/msn/symbols.rs

@@ -1,56 +0,0 @@
-use std::collections::HashMap;
-use std::sync::OnceLock;
-
-const SYMBOL_IDS_RAW: &str = include_str!("symbol_ids.tsv");
-
-static SYMBOL_IDS: OnceLock<HashMap<&'static str, &'static str>> = OnceLock::new();
-
-fn symbol_ids() -> &'static HashMap<&'static str, &'static str> {
-    SYMBOL_IDS.get_or_init(|| {
-        SYMBOL_IDS_RAW
-            .lines()
-            .filter_map(|line| line.split_once('\t'))
-            .collect()
-    })
-}
-
-pub(crate) fn ticker_from_symbol(symbol: &str) -> Option<String> {
-    let trimmed = symbol.trim();
-    if trimmed.is_empty() {
-        return None;
-    }
-    Some(
-        trimmed
-            .split('.')
-            .next()
-            .unwrap_or(trimmed)
-            .trim()
-            .to_uppercase(),
-    )
-}
-
-pub(crate) fn resolve_msn_id(symbol: &str) -> Option<&'static str> {
-    let ticker = ticker_from_symbol(symbol)?;
-    symbol_ids().get(ticker.as_str()).copied()
-}
-
-pub(crate) fn normalized_symbol(requested: &str, fallback_ticker: &str) -> String {
-    let trimmed = requested.trim().to_uppercase();
-    if trimmed.contains('.') || fallback_ticker.is_empty() {
-        trimmed
-    } else {
-        format!("{}.JK", fallback_ticker.trim().to_uppercase())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::resolve_msn_id;
-
-    #[test]
-    fn resolves_symbol_variants() {
-        assert_eq!(resolve_msn_id("BBCA"), Some("bn91jc"));
-        assert_eq!(resolve_msn_id("bbca.jk"), Some("bn91jc"));
-        assert_eq!(resolve_msn_id("INVALID"), None);
-    }
-}