chore(tr): add option to resolve rpc to install dep source (#360)

Adds an option to the `ResolveDependencies` RPC to instruct the resolver
to
download dependency source code.

- [x] I ran `make setup && make` to update the generated code after
editing a `.atd` file (TODO: have a CI check)
- [x] I made sure we're still backward compatible with old versions of
the CLI.
For example, the Semgrep backend need to still be able to *consume* data
	  generated by Semgrep 1.50.0.
See
https://atd.readthedocs.io/en/latest/atdgen-tutorial.html#smooth-protocol-upgrades
	  Note that the types related to the semgrep-core JSON output or the
	  semgrep-core RPC do not need to be backward compatible!

Author: bkettle

semgrep_output_v1.atd

@@ -2385,6 +2385,11 @@ type unresolved_subproject
    errors: sca_error list;
 }
 
+type resolve_dependencies_params <python decorator="dataclass(frozen=True)"> = {
+  dependency_sources: dependency_source list;
+  download_dependency_source_code: bool;
+}
+
 (* Resolution can either succeed or fail, but in either case errors can be
  * produced (e.g. one resolution method might fail while a worse one succeeds,
  * lockfile parsing might partially fail but recover and still produce results).
@@ -2466,7 +2471,7 @@ type function_call <python decorator="dataclass(frozen=True)"> = [
      the RPC pipe.
   *)
   | CallValidate of fpath
-  | CallResolveDependencies of dependency_source list
+  | CallResolveDependencies of resolve_dependencies_params
   | CallUploadSymbolAnalysis of ((* token *) string * (* scan_id *) int * symbol_analysis)
   | CallDumpRulePartitions of dump_rule_partitions_params
   | CallGetTargets of scanning_roots