docs(targets): document built-in and env droid aliases

- add README guidance for ccsd argv[0] auto-target behavior

- document CCS_DROID_ALIASES runtime extension in architecture docs

README.md

@@ -141,6 +141,17 @@ ccs ollama    # Local Ollama (no API key needed)
 ccs glm       # GLM (API key)
 ```
 
+### Droid Alias (`argv[0]` pattern)
+
+By default, invoking CCS as `ccsd` auto-selects the Droid target:
+
+```bash
+ln -s "$(command -v ccs)" /usr/local/bin/ccsd
+ccsd glm
+```
+
+Need additional alias names? Set `CCS_DROID_ALIASES` as a comma-separated list (for example: `CCS_DROID_ALIASES=ccs-droid,mydroid`).
+
 ### Kiro Auth Methods
 
 `ccs kiro --auth` defaults to AWS Builder ID Device OAuth (best support for AWS org accounts).

docs/system-architecture/target-adapters.md

@@ -355,6 +355,7 @@ ccs --target droid glm
 
 ```bash
 # Create alias/symlink to auto-select droid target
+# Built-in alias: ccsd
 ln -s /path/to/ccs /path/to/ccsd
 
 # Usage
@@ -365,6 +366,8 @@ ccsd glm
 
 On Windows, `ccsd.cmd`, `ccsd.bat`, `ccsd.ps1`, and `ccsd.exe` wrappers are also recognized.
 
+Additional alias names can be configured at runtime via `CCS_DROID_ALIASES` (comma-separated). Example: `CCS_DROID_ALIASES=ccs-droid,mydroid`.
+
 ---
 
 ## Registry and Lookup