Add compile-time flag to disable dialog event package

[Copilot]

Description

Introduces PJSUA_HAS_DLG_EVENT_PKG compile-time configuration to conditionally enable/disable RFC 4235 dialog event package initialization.

Changes:

• Added PJSUA_HAS_DLG_EVENT_PKG macro in pjsip/include/pjsua-lib/pjsua.h (default: 1)
• Wrapped pjsip_dlg_event_init_module() call in pjsip/src/pjsua-lib/pjsua_core.c with #if PJSUA_HAS_DLG_EVENT_PKG

Usage:

Users with existing dialog event server implementations can disable the built-in client:

// In pjlib/include/pj/config_site.h
#define PJSUA_HAS_DLG_EVENT_PKG 0

Motivation and Context

Dialog event package (RFC 4235) client support added in #3754 conflicts with existing user implementations of the server side. This flag allows users to opt-out while maintaining backward compatibility (enabled by default).

The configuration is placed at the PJSUA level (in pjsua.h) following the pattern of other PJSUA configuration macros like PJSUA_HAS_VIDEO and PJSUA_HAS_SIPREC, making it consistent with the high-level API architecture.

How Has This Been Tested?

• Built successfully with default configuration (enabled)
• Built successfully with PJSUA_HAS_DLG_EVENT_PKG=0 (disabled)
• Verified pjsua runtime behavior in both configurations
• Confirmed mod-dlg_event module registration reflects configuration state

Screenshots (if appropriate):

N/A

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the CODING STYLE of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Dialog event client implementation conflicts with user's server implementation</issue_title>
<issue_description>### Describe the bug

In #3754, we add support for dialog event subscription, but for client only. But this will conflict with users that have already implemented the server side of the feature.

Steps to reproduce

N/A

PJSIP version

2.16

Context

N/A

Log, call stack, etc

N/A
```</issue_description>

<agent_instructions>Introduce a compile-time setting to enable/disable `pjsip_dlg_event_init_module()` (default is enabled).
</agent_instructions>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

• Fixes Dialog event client implementation conflicts with user's server implementation #4809

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[sauwming]

@copilot: The setting should be at pjsua level (i.e. in pjsua.h)

[sauwming]

@copilot: The setting should be at pjsua level (i.e. in pjsua.h)

[Copilot]

Done. Moved the configuration macro from sip_config.h to pjsua.h and renamed it to PJSUA_HAS_DLG_EVENT_PKG. (commit 6a2dfba)

[sauwming]

The failed CI test seems to be unrelated to the PR:

• ioq read

==9966==ERROR: AddressSanitizer: heap-use-after-free on address 0x515000031230 at pc 0x7efcdf0fb42e bp 0x7efcd7be8b40 sp 0x7efcd7be82e8
READ of size 12 at 0x515000031230 thread T3
    #2 0x556e04b1cfd8 in pj_strdup ../include/pj/string_i.h:43
    #3 0x556e04415889 in pjrpid_add_element ../src/pjsip-simple/rpid.c:128
    #4 0x556e0440f964 in pjsip_pres_create_pidf ../src/pjsip-simple/presence_body.c:147
    #5 0x556e04409fda in pres_create_msg_body ../src/pjsip-simple/presence.c:494
    #6 0x556e0440a404 in pjsip_pres_notify ../src/pjsip-simple/presence.c:550
    #7 0x556e0440adba in pres_on_evsub_rx_refresh ../src/pjsip-simple/presence.c:697
    #8 0x556e04401c98 in on_tsx_state_uas ../src/pjsip-simple/evsub.c:2187
    #9 0x556e04402cac in mod_evsub_on_tsx_state ../src/pjsip-simple/evsub.c:2346
    #10 0x556e044ae01f in pjsip_dlg_on_tsx_state ../src/pjsip/sip_dialog.c:2252
    #11 0x556e044af654 in mod_ua_on_tsx_state ../src/pjsip/sip_ua_layer.c:186
    #12 0x556e04492c6b in tsx_set_state ../src/pjsip/sip_transaction.c:1481
    #13 0x556e0449ad70 in tsx_on_state_null ../src/pjsip/sip_transaction.c:2890
    #14 0x556e0449655c in pjsip_tsx_recv_msg ../src/pjsip/sip_transaction.c:2107
    #15 0x556e044ac040 in pjsip_dlg_on_rx_request ../src/pjsip/sip_dialog.c:1882
    #16 0x556e044b15d3 in mod_ua_on_rx_request ../src/pjsip/sip_ua_layer.c:745
    #17 0x556e0443fdde in pjsip_endpt_process_rx_data ../src/pjsip/sip_endpoint.c:961
    #18 0x556e0444071e in endpt_on_rx_msg ../src/pjsip/sip_endpoint.c:1113
    #19 0x556e0445e51d in pjsip_tpmgr_receive_packet ../src/pjsip/sip_transport.c:2465
    #20 0x556e04461827 in udp_on_read_complete ../src/pjsip/sip_transport_udp.c:193
    #21 0x556e04add168 in ioqueue_dispatch_read_event ../src/pj/ioqueue_common_abs.c:777
    #22 0x556e04ae320a in pj_ioqueue_poll ../src/pj/ioqueue_select.c:1093

0x515000031230 is located 176 bytes inside of 512-byte region [0x515000031180,0x515000031380)
freed by thread T3 here:
    #4 0x556e04af90ad in pj_pool_release ../include/pj/pool_i.h:155
    #5 0x556e0440a976 in pres_on_evsub_state ../src/pjsip-simple/presence.c:641
    #6 0x556e043f945a in set_state ../src/pjsip-simple/evsub.c:630
    #7 0x556e04401aba in on_tsx_state_uas ../src/pjsip-simple/evsub.c:2174
    #8 0x556e04402cac in mod_evsub_on_tsx_state ../src/pjsip-simple/evsub.c:2346
    #9 0x556e044ae01f in pjsip_dlg_on_tsx_state ../src/pjsip/sip_dialog.c:2252
    #10 0x556e044af654 in mod_ua_on_tsx_state ../src/pjsip/sip_ua_layer.c:186
    #11 0x556e04492c6b in tsx_set_state ../src/pjsip/sip_transaction.c:1481
    #12 0x556e0449ad70 in tsx_on_state_null ../src/pjsip/sip_transaction.c:2890
    #13 0x556e0449655c in pjsip_tsx_recv_msg ../src/pjsip/sip_transaction.c:2107
    #14 0x556e044ac040 in pjsip_dlg_on_rx_request ../src/pjsip/sip_dialog.c:1882
    #15 0x556e044b15d3 in mod_ua_on_rx_request ../src/pjsip/sip_ua_layer.c:745
    #16 0x556e0443fdde in pjsip_endpt_process_rx_data ../src/pjsip/sip_endpoint.c:961
    #17 0x556e0444071e in endpt_on_rx_msg ../src/pjsip/sip_endpoint.c:1113
    #18 0x556e0445e51d in pjsip_tpmgr_receive_packet ../src/pjsip/sip_transport.c:2465
    #19 0x556e04461827 in udp_on_read_complete ../src/pjsip/sip_transport_udp.c:193
    #20 0x556e04add168 in ioqueue_dispatch_read_event ../src/pj/ioqueue_common_abs.c:777
    #21 0x556e04ae320a in pj_ioqueue_poll ../src/pj/ioqueue_select.c:1093

• ioq unreg

   3  Id: af0.ff0 Suspend: 0 Teb: 0075a000 Unfrozen "unittest00A29B14"
ChildEBP RetAddr      
02b8fad8 002c0ede     KERNELBASE!Sleep+0xf
02b8fae4 0029b345     pjlib_test_i386_Win32_vc14_Release!pj_thread_sleep+0x1e
02b8fb54 0029b643     pjlib_test_i386_Win32_vc14_Release!perform_unreg_test+0x335
02b8fbb0 0029b474     pjlib_test_i386_Win32_vc14_Release!udp_ioqueue_unreg_test_imp+0x1c3
02b8fbb8 002cde62     pjlib_test_i386_Win32_vc14_Release!udp_ioqueue_unreg_test+0x14
02b8fc14 002ce12f     pjlib_test_i386_Win32_vc14_Release!run_test_case+0xa2