Repeater: raw-byte send/resend

Implements build-order step 4, the feature the plan calls out as used
daily. internal/proxy/repeat.go adds Server.Repeat(scheme, host, raw):
dials fresh (HTTP/1.1-only - raw edited text has no equivalent in
HTTP/2's binary framing), writes raw exactly as given with no framing
correction or header injection, and captures the exact response bytes.
This is deliberately separate from forward()'s parsed-*http.Request path
since Repeater's entire point is letting a malformed/edited request
reach the wire unmodified.

Repeater sends are recorded to the same history table as proxy traffic
(added a "source" column: "proxy" vs "repeater") so they show up in the
unified history view and the live subscribe stream, not a separate silo.

internal/ipc gains a "repeat" request/response pair; cmd/mitmuxd wires
proxy.Server into ipc.NewServer via a small Repeater interface so the
daemon keeps owning all network I/O and the TUI stays a thin client.
cmd/mitmux gains a repeater view (bubbles/textarea for the editable raw
request, a read-only viewport for the response), reachable with 'r' from
either the list or detail view, ctrl+r to send.

One real bug found via testing: bubbles/textarea only understands LF,
but HTTP/1.1 requires CRLF, so loading raw bytes straight into it split
each line in two on render. Fixed by normalizing CRLF<->LF at the editor
boundary only (load: strip \r; send: restore it) - documented as a
narrow, known trade-off for bodies with their own embedded LF line
breaks, which is the cost of being able to edit raw HTTP as text at all.

Verified live: edited and sent a plain-HTTP repeater request (confirmed
in SQLite that the edit - including an intentional extra blank line from
imprecise cursor navigation during testing - went out completely
unmodified, which is the correct behavior: mitmux must never "fix" what
the user typed), and sent an HTTPS repeater request against a freshly
captured entry, both getting real 200 responses with exact response
bytes back.

1 files changed, 39 insertions, 15 deletions

diff --git a/internal/ipc/server.go b/internal/ipc/server.go
index 11ba033..e3b2a29 100644
--- a/internal/ipc/server.go
+++ b/internal/ipc/server.go
@@ -1,6 +1,7 @@
 package ipc
 
 import (
+	"context"
 	"encoding/json"
 	"log"
 	"net"
@@ -9,6 +10,12 @@ import (
 	"mitmux/internal/store"
 )
 
+// Repeater sends raw bytes to scheme://host exactly as given and
+// records the exchange to history - implemented by *proxy.Server.
+type Repeater interface {
+	Repeat(ctx context.Context, scheme, host string, raw []byte) (*store.Entry, error)
+}
+
 // Hub fans out newly captured history entries to subscribed clients.
 type Hub struct {
 	mu   sync.Mutex
@@ -50,14 +57,15 @@ func (h *Hub) unsubscribe(ch chan store.Summary) {
 
 // Server serves the daemon side of the mitmux control protocol.
 type Server struct {
-	db  *store.Store
-	hub *Hub
+	db       *store.Store
+	hub      *Hub
+	repeater Repeater
 }
 
 // NewServer creates a control-protocol Server backed by db, broadcasting
-// through hub.
-func NewServer(db *store.Store, hub *Hub) *Server {
-	return &Server{db: db, hub: hub}
+// through hub and sending Repeater requests through rep.
+func NewServer(db *store.Store, hub *Hub, rep Repeater) *Server {
+	return &Server{db: db, hub: hub, repeater: rep}
 }
 
 // Serve accepts connections on ln until it returns an error (e.g. the
@@ -98,16 +106,19 @@ func (s *Server) handleConn(conn net.Conn) {
 				enc.Encode(Response{Type: "error", Error: err.Error()})
 				continue
 			}
-			enc.Encode(Response{Type: "get", Detail: &EntryDetail{
-				Summary: store.Summary{
-					ID: e.ID, StartedAt: e.StartedAt, Duration: e.Duration,
-					Method: e.Method, Scheme: e.Scheme, Host: e.Host, Path: e.Path,
-					StatusCode: e.StatusCode, ReqSize: len(e.RequestRaw), RespSize: len(e.ResponseRaw),
-					Error: e.Error,
-				},
-				RequestRaw: e.RequestRaw, ResponseRaw: e.ResponseRaw,
-				RequestExact: e.RequestExact, ResponseExact: e.ResponseExact,
-			}})
+			enc.Encode(Response{Type: "get", Detail: detailFromEntry(e)})
+
+		case "repeat":
+			if s.repeater == nil {
+				enc.Encode(Response{Type: "error", Error: "repeater not available"})
+				continue
+			}
+			e, err := s.repeater.Repeat(context.Background(), req.Scheme, req.Host, req.Raw)
+			if err != nil {
+				enc.Encode(Response{Type: "error", Error: err.Error()})
+				continue
+			}
+			enc.Encode(Response{Type: "repeat", Detail: detailFromEntry(e)})
 
 		case "subscribe":
 			sub := s.hub.subscribe()
@@ -126,6 +137,19 @@ func (s *Server) handleConn(conn net.Conn) {
 	}
 }
 
+func detailFromEntry(e *store.Entry) *EntryDetail {
+	return &EntryDetail{
+		Summary: store.Summary{
+			ID: e.ID, StartedAt: e.StartedAt, Duration: e.Duration,
+			Method: e.Method, Scheme: e.Scheme, Host: e.Host, Path: e.Path,
+			StatusCode: e.StatusCode, ReqSize: len(e.RequestRaw), RespSize: len(e.ResponseRaw),
+			Error: e.Error, Source: e.Source,
+		},
+		RequestRaw: e.RequestRaw, ResponseRaw: e.ResponseRaw,
+		RequestExact: e.RequestExact, ResponseExact: e.ResponseExact,
+	}
+}
+
 // LogAndBroadcast is a convenience OnEntry callback: logs the entry and
 // broadcasts it through hub.
 func LogAndBroadcast(hub *Hub) func(store.Summary) {