feat: walk function body for pruning

feat: prune unreachable symbols after stg phase

feat: handle export charms, save exported functions per unit

feat: parse symbol charms

refac: remove separate errors in walker

test: working integration tests for genc backend

feat: parse loop and for num range statements

fix: ast format for array type specifier

test: genc integration test now invoke cc

test: working parser test suite

refac: (wip) parser error recovery

refac: (wip) parse via cli and parser tests

refac: (wip) integration tests for parser

feat: store compilation errors in centralized source pool

test: harness for C backend

feat: working short if with return

test: validate integration tests, new failing test case

test: more vm32b integration test cases

feat: working harness for vm32b integration tests

chore: remove prototype for bytecode vm

feat: kvx encode format for bytecode programs