Update progress info and start welcome info (#3768)

### What problem does this PR solve?

_Briefly describe what this PR aims to solve. Include background context
that will help reviewers understand the purpose of the PR._

### Type of change

- [x] Refactoring

---------

Signed-off-by: jinhai <haijin.chn@gmail.com>

rag/app/paper.py

@@ -27,7 +27,9 @@ class Pdf(PdfParser):
 
     def __call__(self, filename, binary=None, from_page=0,
                  to_page=100000, zoomin=3, callback=None):
-        callback(msg="OCR is running...")
+        from timeit import default_timer as timer
+        start = timer()
+        callback(msg="OCR started")
         self.__images__(
             filename if not binary else binary,
             zoomin,
@@ -35,21 +37,24 @@ class Pdf(PdfParser):
             to_page,
             callback
         )
-        callback(msg="OCR finished.")
+        callback(msg="OCR finished ({:.2f}s)".format(timer() - start))
 
-        from timeit import default_timer as timer
         start = timer()
         self._layouts_rec(zoomin)
-        callback(0.63, "Layout analysis finished")
+        callback(0.63, "Layout analysis ({:.2f}s)".format(timer() - start))
         logging.debug(f"layouts cost: {timer() - start}s")
+
+        start = timer()
         self._table_transformer_job(zoomin)
-        callback(0.68, "Table analysis finished")
+        callback(0.68, "Table analysis ({:.2f}s)".format(timer() - start))
+
+        start = timer()
         self._text_merge()
         tbls = self._extract_table_figure(True, zoomin, True, True)
         column_width = np.median([b["x1"] - b["x0"] for b in self.boxes])
         self._concat_downward()
         self._filter_forpages()
-        callback(0.75, "Text merging finished.")
+        callback(0.75, "Text merged ({:.2f}s)".format(timer() - start))
 
         # clean mess
         if column_width < self.page_images[0].size[0] / zoomin / 2: