Creating 2 verbs with the same name/signature causes panic

[wesbillman]

If time.go is updated to have duplicate verbs:

// Time returns the current time.
//
//ftl:export
func Time(ctx context.Context, req TimeRequest) (TimeResponse, error) {
	return TimeResponse{Time: time.Now()}, nil
}

// Time returns the current time.
//
//ftl:export
func Time(ctx context.Context, req TimeRequest) (TimeResponse, error) {
	return TimeResponse{Time: time.Now()}, nil
}

ftl dev . will panic:

info: Starting FTL with 1 controller(s)
info:time: Building module
panic: interface conversion: types.Object is nil, not *types.Func

goroutine 140 [running]:
github.com/TBD54566975/ftl/go-runtime/compile.visitFuncDecl(0x140003a6f00, 0x140004023f0)
	/Users/wesbillman/dev/ftl/go-runtime/compile/schema.go:473 +0x9b4
github.com/TBD54566975/ftl/go-runtime/compile.ExtractModuleSchema.func1({0x103df2550?, 0x140004023f0?}, 0x14000357ae0)
	/Users/wesbillman/dev/ftl/go-runtime/compile/schema.go:126 +0x1c8
github.com/TBD54566975/ftl/internal/goast.Visit(...)
	/Users/wesbillman/dev/ftl/internal/goast/visitor.go:17
github.com/TBD54566975/ftl/internal/goast.visitList[...]({0x14000ac6100?, 0x140004deec0?, 0x102b189a0?}, 0x140004deec0?)
	/Users/wesbillman/dev/ftl/internal/goast/visitor.go:558 +0xe4
github.com/TBD54566975/ftl/go-runtime/compile.ExtractModuleSchema.Visit.func2()
	/Users/wesbillman/dev/ftl/internal/goast/visitor.go:535 +0x2f8
github.com/TBD54566975/ftl/go-runtime/compile.ExtractModuleSchema.func1({0x103df25c8?, 0x1400001a000?}, 0x140001d2e08?)
	/Users/wesbillman/dev/ftl/go-runtime/compile/schema.go:145 +0x2b8
github.com/TBD54566975/ftl/internal/goast.Visit(...)
	/Users/wesbillman/dev/ftl/internal/goast/visitor.go:17
github.com/TBD54566975/ftl/go-runtime/compile.ExtractModuleSchema({0x1400031a990, 0x2a})
	/Users/wesbillman/dev/ftl/go-runtime/compile/schema.go:110 +0x66c
github.com/TBD54566975/ftl/go-runtime/compile.Build({0x103dfa1b8, 0x140004044e0}, {0x1400031a990, 0x2a}, 0x140003ea4c0)
	/Users/wesbillman/dev/ftl/go-runtime/compile/build.go:102 +0x338
github.com/TBD54566975/ftl/buildengine.buildGoModule({0x103dfa1b8?, 0x140004044e0?}, 0x104a4a430?, {{{0x1400031a990, 0x2a}, {0x140001a13c8, 0x2}, {0x140001a13cc, 0x4}, {0x140001a13d0, ...}, ...}, ...})
	/Users/wesbillman/dev/ftl/buildengine/build_go.go:12 +0x3c
github.com/TBD54566975/ftl/buildengine.buildModule({0x103dfa1f0, 0x140001a59a0}, 0x140003ea4c0, {{{0x1400031a990, 0x2a}, {0x140001a13c8, 0x2}, {0x140001a13cc, 0x4}, {0x140001a13d0, ...}, ...}, ...})
	/Users/wesbillman/dev/ftl/buildengine/build.go:34 +0x3c0
github.com/TBD54566975/ftl/buildengine.Build({0x103dfa1f0?, 0x140001a59a0?}, 0x14000346540?, {0x103dfa848?, 0x14000346540?})
	/Users/wesbillman/dev/ftl/buildengine/build.go:19 +0x94
github.com/TBD54566975/ftl/buildengine.(*Engine).build(0x1400021c080, {0x103dfa1f0, 0x140001a59a0}, {0x14000243200, 0x4}, 0x14000444c00, 0x14000151e60)
	/Users/wesbillman/dev/ftl/buildengine/engine.go:474 +0x29c
github.com/TBD54566975/ftl/buildengine.(*Engine).buildWithCallback.func1()
	/Users/wesbillman/dev/ftl/buildengine/engine.go:426 +0x94
golang.org/x/sync/errgroup.(*Group).Go.func1()
	/Users/wesbillman/go/pkg/mod/golang.org/x/[email protected]/errgroup/errgroup.go:78 +0x58
created by golang.org/x/sync/errgroup.(*Group).Go in goroutine 169
	/Users/wesbillman/go/pkg/mod/golang.org/x/[email protected]/errgroup/errgroup.go:75 +0x98
[Error - 11:01:44 AM] The ftl languge server server crashed 5 times in the last 3 minutes. The server will not be restarted. See the output for more information.
[Error - 11:01:44 AM] Server process exited with code 2.