docs(option): rename /list/roots → /list/symbols + nav label fix

User reported https://userfrm.github.io/ThetaDataDx/historical/option/list/roots showed `option_list_roots` H1 / title with `option_list_symbols` code examples in the body. Page URL slug stayed `roots` after the SDK rename to `option_list_symbols`, leaving the public docs page internally inconsistent.

- `docs-site/docs/historical/option/list/roots.md` → `symbols.md` (git mv preserves history).
- H1 + frontmatter title + description: `option_list_roots` → `option_list_symbols`.
- Page prose: dropped the `(roots)` parenthetical from the first paragraph and the "legacy 'roots' term preserved in URL slug" note — there is no legacy slug anymore.
- `docs-site/docs/historical/option/index.md`: `./list/roots` → `./list/symbols` link + "List Roots" → "List Symbols" label.
- `docs-site/docs/.vitepress/config.ts`: nav-bar label `Roots` → `Symbols` (the link was already pointing at `/list/symbols`).

`docs-site` build will regenerate `.vitepress/dist/` next deploy. Inbound links to the old URL will 404; that is the cost of the rename — the URL was internally lying about its content for the entire v9.1.0 / v10.0.0 wave.

Pre-push pipeline: cargo run -p thetadatadx --bin generate_sdk_surfaces --check, python3 scripts/check_docs_consistency.py — both green.

Author: userFRM

docs-site/docs/.vitepress/config.ts

@@ -128,7 +128,7 @@ export default withMermaid(defineConfig({
                 text: 'List',
                 collapsed: true,
                 items: [
-                  { text: 'Roots', link: '/historical/option/list/roots' },
+                  { text: 'Symbols', link: '/historical/option/list/symbols' },
                   { text: 'Dates', link: '/historical/option/list/dates' },
                   { text: 'Strikes', link: '/historical/option/list/strikes' },
                   { text: 'Expirations', link: '/historical/option/list/expirations' },

docs-site/docs/historical/option/index.md

@@ -22,11 +22,11 @@ Option contracts are identified by four parameters:
 
 ## Endpoint Categories
 
-### [List](./list/roots) (5 endpoints)
+### [List](./list/symbols) (5 endpoints)
 
 Discover available symbols, expirations, strikes, dates, and contracts.
 
-- [List Roots](./list/roots) - all option underlying symbols
+- [List Symbols](./list/symbols) - all option underlying symbols
 - [List Dates](./list/dates) - available dates for a contract
 - [List Strikes](./list/strikes) - strike prices for an expiration
 - [List Expirations](./list/expirations) - expiration dates for an underlying

…ite/docs/historical/option/list/roots.md …e/docs/historical/option/list/symbols.mddocs-site/docs/historical/option/list/roots.md renamed to docs-site/docs/historical/option/list/symbols.md docs-site/docs/historical/option/list/roots.md renamed to docs-site/docs/historical/option/list/symbols.md

@@ -1,13 +1,13 @@
 ---
-title: option_list_roots
+title: option_list_symbols
 description: List all available option underlying symbols.
 ---
 
-# option_list_roots
+# option_list_symbols
 
 <TierBadge tier="free" />
 
-List all available option underlying symbols (roots). Use this to discover which tickers have option chains available in ThetaData.
+List all available option underlying symbols. Use this to discover which tickers have option chains available in ThetaData.
 
 ## Code Example
 
@@ -60,4 +60,4 @@ None.
 ## Notes
 
 - Returns all underlying symbols, not individual contracts. Use [option_list_expirations](./expirations) and [option_list_strikes](./strikes) to drill into a specific chain.
-- The Rust SDK method is `option_list_symbols`. The legacy "roots" term is preserved in this page's URL slug for inbound-link stability; the SDK and protobuf surface use `symbol` exclusively.
+- The Rust SDK method is `option_list_symbols`. The SDK and protobuf surface use `symbol` exclusively.