refactor: move ParseTree out of valueobject to enable CGO-free client builds

[Anthony-Bible]

Problem

ParseTree currently lives in internal/domain/valueobject/parse_tree.go and directly imports github.com/alexaandru/go-tree-sitter-bare, a CGO dependency. Because Go compiles whole packages, anything that imports valueobject pulls in the tree-sitter CGO requirement — even code that has nothing to do with parsing.

This blocks building the CLI client (cmd/client) as a static, CGO-free binary. The dependency chain is:

client → internal/application/dto → dto/connector.go → internal/domain/valueobject → parse_tree.go → go-tree-sitter-bare (CGO)

Goal

Move ParseTree (and its tree-sitter dependency) out of the domain valueobject package and into the adapter layer where it belongs (e.g. internal/adapter/outbound/treesitter). This would:

• Keep the domain layer free of infrastructure dependencies
• Allow cmd/client to be built with CGO_ENABLED=0 as a portable static binary
• Better align with the hexagonal architecture (CGO/tree-sitter is an infrastructure concern, not a domain concept)

Scope

• Move internal/domain/valueobject/parse_tree.go → internal/adapter/outbound/treesitter/
• Update all references across chunking adapters and treesitter interfaces
• Restore CGO_ENABLED=0 in make build-client and cross-compile targets

Notes

Workaround applied in #: changed make build-client to use CGO_ENABLED=1 so the build works in the interim.