Added features

Added: 
Project Overview TUI 
Build Cache / Dirty Detection
Post-Build Hooks
gbuild status

src/cache.c

@@ -0,0 +1,65 @@
+#include "cache.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+
+/* Name of the dotfile kept inside each cloned repo. */
+#define CACHE_FILENAME ".gbuild_cache"
+
+/* ----------------------------------------------------------------- helpers */
+
+static void cache_path(char *out, size_t n, const char *repo_path)
+{
+    snprintf(out, n, "%s/" CACHE_FILENAME, repo_path);
+}
+
+/* ----------------------------------------------------------------- public API */
+
+int cache_read(const char *repo_path, char *out, size_t n)
+{
+    char path[1024];
+    cache_path(path, sizeof(path), repo_path);
+
+    out[0] = '\0';
+
+    FILE *f = fopen(path, "r");
+    if (!f)
+        return -1;   /* file doesn't exist yet — not an error, just a cache miss */
+
+    char buf[CACHE_HASH_LEN] = {0};
+    int ok = (fgets(buf, sizeof(buf), f) != NULL);
+    fclose(f);
+
+    if (!ok || buf[0] == '\0')
+        return -1;
+
+    /* strip trailing newline */
+    size_t l = strlen(buf);
+    if (l > 0 && buf[l - 1] == '\n')
+        buf[--l] = '\0';
+
+    if (l == 0)
+        return -1;
+
+    strncpy(out, buf, n - 1);
+    out[n - 1] = '\0';
+    return 0;
+}
+
+int cache_write(const char *repo_path, const char *hash)
+{
+    char path[1024];
+    cache_path(path, sizeof(path), repo_path);
+
+    FILE *f = fopen(path, "w");
+    if (!f) {
+        fprintf(stderr, "[WARN ] cache_write: cannot open %s: %s\n",
+                path, strerror(errno));
+        return -1;
+    }
+
+    fprintf(f, "%s\n", hash);
+    fclose(f);
+    return 0;
+}